Catalyst 6500 Release 12.2SX Software Configuration Guide

Configuring Local SPAN, RSPAN, and ERSPAN

This chapter describes how to configure local Switched Port Analyzer (SPAN), remote SPAN (RSPAN), and Encapsulated RSPAN (ERSPAN) in Cisco IOS Release 12.2SX.

Note•For complete syntax and usage information for the commands used in this chapter, see the Cisco IOS Master Command List, at this URL:

http://www.cisco.com/en/US/docs/ios/mcl/allreleasemcl/all_book.html

•SPA ports and FlexWAN ports do not support SPAN, RSPAN, or ERSPAN.

Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information), see the documents listed on this page:

http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html

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This chapter consists of these sections:

•Understanding Local SPAN, RSPAN, and ERSPAN

•Local SPAN, RSPAN, and ERSPAN Configuration Guidelines and Restrictions

•Configuring Local SPAN, RSPAN, and ERSPAN

Understanding Local SPAN, RSPAN, and ERSPAN

These sections describe how local SPAN, RSPAN, and ERSPAN work:

•Local SPAN, RSPAN, and ERSPAN Overview

•Local SPAN, RSPAN, and ERSPAN Sources

•Local SPAN, RSPAN, and ERSPAN Destinations

Local SPAN, RSPAN, and ERSPAN Overview

SPAN copies traffic from one or more CPUs, one or more ports, one or more EtherChannels, or one or more VLANs, and sends the copied traffic to one or more destinations for analysis by a network analyzer such as a SwitchProbe device or other Remote Monitoring (RMON) probe. Traffic can also be sent to the processor for packet capture by the Mini Protocol Analyzer, as described in Chapter 72 "Using the Mini Protocol Analyzer."

SPAN does not affect the switching of traffic on sources. You must dedicate the destination for SPAN use. The SPAN-generated copies of traffic compete with user traffic for switch resources.

These sections provide an overview of local SPAN, RSPAN, and ERSPAN:

•Local SPAN Overview

•RSPAN Overview

•ERSPAN Overview

•Understanding the Traffic Monitored at SPAN Sources

Local SPAN Overview

A local SPAN session is an association of source ports and source VLANs with one or more destinations. You configure a local SPAN session on a single switch. Local SPAN does not have separate source and destination sessions.

Local SPAN sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. Local SPAN sessions do not copy locally sourced RSPAN GRE-encapsulated traffic from source ports.

Each local SPAN session can have either ports or VLANs as sources, but not both.

Local SPAN copies traffic from one or more source ports in any VLAN or from one or more VLANs to a destination for analysis (see Figure 68-1). For example, as shown in Figure 68-1, all traffic on Ethernet port 5 (the source port) is copied to Ethernet port 10. A network analyzer on Ethernet port 10 receives all traffic from Ethernet port 5 without being physically attached to Ethernet port 5.

Figure 68-1 Example SPAN Configuration

RSPAN Overview

RSPAN supports source ports, source VLANs, and destinations on different switches, which provides remote monitoring of multiple switches across your network (see Figure 68-2). RSPAN uses a Layer 2 VLAN to carry SPAN traffic between switches.

RSPAN consists of an RSPAN source session, an RSPAN VLAN, and an RSPAN destination session. You separately configure RSPAN source sessions and destination sessions on different switches. To configure an RSPAN source session on one switch, you associate a set of source ports or VLANs with an RSPAN VLAN. To configure an RSPAN destination session on another switch, you associate the destinations with the RSPAN VLAN.

The traffic for each RSPAN session is carried as Layer 2 nonroutable traffic over a user-specified RSPAN VLAN that is dedicated for that RSPAN session in all participating switches. All participating switches must be trunk-connected at Layer 2.

RSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. RSPAN source sessions do not copy locally sourced RSPAN GRE-encapsulated traffic from source ports.

Each RSPAN source session can have either ports or VLANs as sources, but not both.

The RSPAN source session copies traffic from the source ports or source VLANs and switches the traffic over the RSPAN VLAN to the RSPAN destination session. The RSPAN destination session switches the traffic to the destinations.

Figure 68-2 RSPAN Configuration

ERSPAN Overview

ERSPAN supports source ports, source VLANs, and destinations on different switches, which provides remote monitoring of multiple switches across your network (see Figure 68-3). ERSPAN uses a GRE tunnel to carry traffic between switches.

ERSPAN consists of an ERSPAN source session, routable ERSPAN GRE-encapsulated traffic, and an ERSPAN destination session. You separately configure ERSPAN source sessions and destination sessions on different switches.

To configure an ERSPAN source session on one switch, you associate a set of source ports or VLANs with a destination IP address, ERSPAN ID number, and optionally with a VRF name. To configure an ERSPAN destination session on another switch, you associate the destinations with the source IP address, ERSPAN ID number, and optionally with a VRF name.

ERSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs. ERSPAN source sessions do not copy locally sourced ERSPAN GRE-encapsulated traffic from source ports.

Each ERSPAN source session can have either ports or VLANs as sources, but not both.

The ERSPAN source session copies traffic from the source ports or source VLANs and forwards the traffic using routable GRE-encapsulated packets to the ERSPAN destination session. The ERSPAN destination session switches the traffic to the destinations.

Figure 68-3 ERSPAN Configuration

Understanding the Traffic Monitored at SPAN Sources

These sections describe the traffic that local SPAN, RSPAN, and ERSPAN sources can monitor:

•Monitored Traffic Direction

•Monitored Traffic Type

•Duplicate Traffic

Monitored Traffic Direction

You can configure local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions to monitor the following traffic:

•Ingress traffic

–Called ingress SPAN.

–Copies traffic received by the sources (ingress traffic).

–Ingress traffic is sent to the supervisor engine SPAN ASIC to be copied.

•Egress traffic

–Called egress SPAN.

–Copies traffic transmitted from the sources (egress traffic).

–Distributed egress SPAN mode—With Release 12.2(33)SXH and later releases, on some fabric-enabled switching modules, egress traffic can be copied locally by the switching module SPAN ASIC and then sent to the SPAN destinations. See the "Distributed Egress SPAN Mode Guidelines and Restrictions" section for information about switching modules that support distributed egress SPAN mode.

–Centralized egress SPAN mode—On all other switching modules, egress traffic is sent to the supervisor engine SPAN ASIC to be copied and is then sent to the SPAN destinations.

•Both

–Copies both the received traffic and the transmitted traffic (ingress and egress traffic).

–Both ingress traffic and egress traffic is sent to the supervisor engine SPAN ASIC to be copied.

Monitored Traffic Type

By default, local SPAN and ERSPAN monitor all traffic, including multicast and bridge protocol data unit (BPDU) frames. RSPAN does not support BPDU monitoring.

Duplicate Traffic

In some configurations, SPAN sends multiple copies of the same source traffic to the destination. For example, in a configuration with a bidirectional SPAN session (both ingress and egress) for two SPAN sources, called s1 and s2, to a SPAN destination, called d1, if a packet enters the switch through s1 and is sent for egress from the switch to s2, ingress SPAN at s1 sends a copy of the packet to SPAN destination d1 and egress SPAN at s2 sends a copy of the packet to SPAN destination d1. If the packet was Layer 2 switched from s1 to s2, both SPAN packets would be the same. If the packet was Layer 3 switched from s1 to s2, the Layer 3 rewrite would alter the source and destination Layer 2 addresses, in which case the SPAN packets would be different.

Local SPAN, RSPAN, and ERSPAN Sources

These sections describe local SPAN, RSPAN, and ERSPAN sources:

•Source CPUs

•Source Ports and EtherChannels

•Source VLANs

Source CPUs

A source CPU is a CPU monitored for traffic analysis. With Release 12.2(33)SXH and later releases, you can configure both the SP CPU and the RP CPU as SPAN sources. These are examples of what you can do with the data generated by CPU monitoring:

•Develop baseline information about CPU traffic.

•Develop information to use when creating control plane policing (CoPP) policies.

•Troubleshoot CPU-related issues (for example, high CPU utilization).

Note•CPU SPAN monitors CPU traffic from the perspective of the ASICs that send and receive the CPU traffic, rather than from onboard the CPUs themselves.

•Traffic to and from the CPU is tagged with VLAN IDs. You can configure source VLAN filtering of the CPU traffic.

Source Ports and EtherChannels

A source port or EtherChannel is a port or EtherChannel monitored for traffic analysis. You can configure both Layer 2 and Layer 3 ports and EtherChannels as SPAN sources. SPAN can monitor one or more source ports or EtherChannels in a single SPAN session. You can configure ports or EtherChannels in any VLAN as SPAN sources. Trunk ports or EtherChannels can be configured as sources and mixed with nontrunk sources.

Note SPAN does not copy the encapsulation from trunk sources. You can configure SPAN destinations as trunks to tag the monitored traffic before it is transmitted for analysis.

Source VLANs

A source VLAN is a VLAN monitored for traffic analysis. VLAN-based SPAN (VSPAN) uses a VLAN as the SPAN source. All the ports and EtherChannels in the source VLANs become sources of SPAN traffic.

Note Layer 3 VLAN interfaces on source VLANs are not sources of SPAN traffic. Traffic that enters a VLAN through a Layer 3 VLAN interface is monitored when it is transmitted from the switch through an egress port or EtherChannel that is in the source VLAN.

Local SPAN, RSPAN, and ERSPAN Destinations

A SPAN destination is a Layer 2 or Layer 3 port or, with Release 12.2(33)SXH and later releases, an EtherChannel, to which local SPAN, RSPAN, or ERSPAN sends traffic for analysis. When you configure a port or EtherChannel as a SPAN destination, it is dedicated for use only by the SPAN feature.

Destination EtherChannels do not support the Port Aggregation Control Protocol (PAgP) or Link Aggregation Control Protocol (LACP) EtherChannel protocols; only the on mode is supported, with all EtherChannel protocol support disabled.

There is no requirement that the member links of a destination EtherChannel be connected to a device that supports EtherChannels. For example, you can connect the member links to separate network analyzers. See Chapter 19 "Configuring EtherChannels," for more information about EtherChannel.

Destinations, by default, cannot receive any traffic. With Release 12.2(33)SXH and later releases, you can configure Layer 2 destinations to receive traffic from any attached devices.

Destinations, by default, do not transmit anything except SPAN traffic. Layer 2 destinations that you have configured to receive traffic can be configured to learn the Layer 2 address of any devices attached to the destination and transmit traffic that is addressed to the devices.

You can configure trunks as destinations, which allows trunk destinations to transmit encapsulated traffic. You can use allowed VLAN lists to configure destination trunk VLAN filtering.

Local SPAN, RSPAN, and ERSPAN Configuration Guidelines and Restrictions

These sections describe local SPAN, RSPAN, and ERSPAN configuration guidelines and restrictions:

•General Guidelines and Restrictions

•Feature Incompatibilities

•Local SPAN, RSPAN, and ERSPAN Session Limits

•Local SPAN, RSPAN, and ERSPAN Interface Limits

•Local SPAN, RSPAN, and ERSPAN Guidelines and Restrictions

•VSPAN Guidelines and Restrictions

•RSPAN Guidelines and Restrictions

•ERSPAN Guidelines and Restrictions

•Distributed Egress SPAN Mode Guidelines and Restrictions

General Guidelines and Restrictions

Use SPAN for troubleshooting. Except in carefully planned topologies, SPAN consumes too many switch and network resources to enable permanently.

Exercise all possible care when enabling and configuring SPAN. The traffic copied by SPAN can impose a significant load on the switch and the network.

To minimize the load, configure SPAN to copy only the specific traffic that you want to analyze. Select sources that carry as little unwanted traffic as possible. For example, a port as a SPAN source might carry less unwanted traffic than a VLAN.

Note To monitor traffic that can be matched with an ACL, consider using VACL capture.

Before enabling SPAN, carefully evaluate the SPAN source traffic rates, and consider the performance implications and possible oversubscription points, which include these:

•SPAN destination

•Fabric channel

•Rewrite/replication engine

•Forwarding engine (PFC/DFC)

To avoid disrupting traffic, do not oversubscribe any of these points in your SPAN topology. Some oversubscription and performance considerations are:

•SPAN doubles traffic internally

•SPAN adds to the traffic being processed by the switch fabric

•SPAN doubles forwarding engine load

•The supervisor engine handles the entire load imposed by egress SPAN (also called transmit SPAN).

Note Egress SPAN should only be enabled for short periods of time during active troubleshooting.

Release 12.2(33)SXH and later releases support distributed egress SPAN, which reduces the load on the supervisor engine.

•The ingress modules handle the load imposed by ingress SPAN sources (also called receive SPAN) on each module. Ingress SPAN adds to rewrite/replication engine load.

Feature Incompatibilities

These feature incompatibilities exist with local SPAN, RSPAN, and ERSPAN:

•In releases where CSCth62957 is not resolved, in PFC3B mode or PFC3BXL mode, the xconnect target_ip_address vc_value encapsulation mpls command might cause traffic to loop continuously with these SPAN configurations:

–If the xconnect target_ip_address vc_value encapsulation mpls command is configured on a physical interface, the CLI prevents configuration of that port as part of a SPAN session.

–If a SPAN session is configured on a physical port and you attempt to configure the xconnect target_ip_address vc_value encapsulation mpls command, the CLI prints a warning that recommends against the configuration.

–If the xconnect target_ip_address vc_value encapsulation mpls command is configured on a physical interface, you should not configure source cpu {rp | sp} in any SPAN session, but the CLI does not enforce any restriction.

–If a SPAN session is configured with source cpu {rp | sp} and you attempt to configure the xconnect target_ip_address vc_value encapsulation mpls command, the CLI does not enforce any restriction.

•In releases where CSCth62957 is resolved, to avoid a configuration that might cause traffic to loop continuously, the CLI enforces these restrictions in PFC3B mode or PFC3BXL mode:

–If the xconnect target_ip_address vc_value encapsulation mpls command is configured on a physical interface, the CLI prevents configuration of that port as part of a SPAN session.

–If a SPAN session is configured on a physical port and you attempt to configure the the xconnect target_ip_address vc_value encapsulation mpls command command on that port, the CLI prints a warning that recommends against the configuration.

–If the the xconnect target_ip_address vc_value encapsulation mpls command command is configured on a physical interface, you cannot configure source cpu {rp | sp} in any SPAN session.

–If a SPAN session is configured with source cpu {rp | sp} and you attempt to configure the xconnect target_ip_address vc_value encapsulation mpls command, the CLI prints a warning that recommends against the configuration.

•Egress SPAN is not supported in egress multicast mode. (CSCsa95965)

•Unknown unicast flood blocking (UUFB) ports cannot be RSPAN or local SPAN egress-only destinations. (CSCsj27695)

•Except in PFC3C mode or PFC3CXL mode, Ethernet over MultiProtocol Label Switching (EoMPLS) ports cannot be SPAN sources. (CSCed51245)

•A port-channel interface (an EtherChannel) can be a SPAN source, but you cannot configure active member ports of an EtherChannel as SPAN source ports. Inactive member ports of an EtherChannel can be configured as SPAN sources but they are put into the suspended state and carry no traffic.

•These features are incompatible with SPAN destinations:

–Private VLANs

–IEEE 802.1X port-based authentication

–Port security

–Spanning Tree Protocol (STP) and related features (PortFast, PortFast BPDU filtering, BPDU Guard, UplinkFast, BackboneFast, EtherChannel Guard, Root Guard, Loop Guard)

–VLAN trunk protocol (VTP)

–Dynamic trunking protocol (DTP)

–IEEE 802.1Q tunneling

Note•SPAN destinations can participate in IEEE 802.3Z flow control.

•IP multicast switching using egress packet replication is not compatible with SPAN. In some cases, egress replication can result in multicast packets not being sent to the SPAN destination port. If you are using SPAN and your switching modules are capable of egress replication, enter the mls ip multicast replication-mode ingress command to force ingress replication.

Local SPAN, RSPAN, and ERSPAN Session Limits

With Release 12.2(33)SXH and later releases, these are the PFC3 local SPAN, RSPAN, and ERSPAN session limits:

Local SPAN, RSPAN, and ERSPAN Interface Limits

With Release 12.2(33)SXH and later releases, these are the PFC3 local SPAN, RSPAN, and ERSPAN source and destination interface limits:

Local SPAN, RSPAN, and ERSPAN Guidelines and Restrictions

These guidelines and restrictions apply to local SPAN, RSPAN, and ERSPAN:

•A SPAN destination that is copying traffic from a single egress SPAN source port sends only egress traffic to the network analyzer. If you configure more than one egress SPAN source port, the traffic that is sent to the network analyzer also includes these types of ingress traffic that were received from the egress SPAN source ports:

–Any unicast traffic that is flooded on the VLAN

–Broadcast and multicast traffic

This situation occurs because an egress SPAN source port receives these types of traffic from the VLAN but then recognizes itself as the source of the traffic and drops it instead of sending it back to the source from which it was received. Before the traffic is dropped, SPAN copies the traffic and sends it to the SPAN destination. (CSCds22021)

•Entering additional monitor session commands does not clear previously configured SPAN parameters. You must enter the no monitor session command to clear configured SPAN parameters.

•Connect a network analyzer to the SPAN destinations.

•Within a SPAN session, all of the SPAN destinations receive all of the traffic from all of the SPAN sources, except when source-VLAN filtering is configured on the SPAN source.

•You can configure destination trunk VLAN filtering to select which traffic is transmitted from the SPAN destination.

•You can configure both Layer 2 LAN ports (LAN ports configured with the switchport command) and Layer 3 LAN ports (LAN ports not configured with the switchport command) as sources or destinations.

•You cannot mix individual source ports and source VLANs within a single session.

•If you specify multiple ingress source ports, the ports can belong to different VLANs.

•Within a session, you cannot configure both VLANs as SPAN sources and do source VLAN filtering. You can configure VLANs as SPAN sources or you can do source VLAN filtering of traffic from source ports and EtherChannels, but not both in the same session.

•You cannot configure source VLAN filtering for internal VLANs.

•When enabled, local SPAN, RSPAN, and ERSPAN use any previously entered configuration.

•When you specify sources and do not specify a traffic direction (ingress, egress, or both), "both" is used by default.

•SPAN copies Layer 2 Ethernet frames, but SPAN does not copy source trunk port ISL or 802.1Q tags. You can configure destinations as trunks to send locally tagged traffic to the traffic analyzer.

Note A destination configured as a trunk tags traffic from a Layer 3 LAN source with the internal VLAN used by the Layer 3 LAN source.

•Local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions do not copy locally sourced RSPAN VLAN traffic from source trunk ports that carry RSPAN VLANs.

•Local SPAN sessions, RSPAN source sessions, and ERSPAN source sessions do not copy locally sourced ERSPAN GRE-encapsulated traffic from source ports.

•With Release 12.2(33)SXH and later, SPAN sessions can share destinations.

•SPAN destinations cannot be SPAN sources.

•Destinations never participate in any spanning tree instance. Local SPAN includes BPDUs in the monitored traffic, so any BPDUs seen on the destination are from the source. RSPAN does not support BPDU monitoring.

•All packets forwarded through the switch for transmission from a port that is configured as an egress SPAN source are copied to the SPAN destination, including packets that do not exit the switch through the egress port because STP has put the egress port into the blocking state, or on an egress trunk port because STP has put the VLAN into the blocking state on the trunk port.

VSPAN Guidelines and Restrictions

Note Local SPAN, RSPAN, and ERSPAN all support VSPAN.

These are VSPAN guidelines and restrictions:

•VSPAN sessions do not support source VLAN filtering.

•For VSPAN sessions with both ingress and egress configured, two packets are forwarded from the destination to the analyzer if the packets get switched on the same VLAN (one as ingress traffic from the ingress port and one as egress traffic from the egress port).

•VSPAN only monitors traffic that leaves or enters Layer 2 ports in the VLAN.

–If you configure a VLAN as an ingress source and traffic gets routed into the monitored VLAN, the routed traffic is not monitored because it never appears as ingress traffic entering a Layer 2 port in the VLAN.

–If you configure a VLAN as an egress source and traffic gets routed out of the monitored VLAN, the routed traffic is not monitored because it never appears as egress traffic leaving a Layer 2 port in the VLAN.

RSPAN Guidelines and Restrictions

These are RSPAN guidelines and restrictions:

•All participating switches must be connected by Layer 2 trunks.

•Any network device that supports RSPAN VLANs can be an RSPAN intermediate device.

•Networks impose no limit on the number of RSPAN VLANs that the networks carry.

•Intermediate network devices might impose limits on the number of RSPAN VLANs that they can support.

•You must configure the RSPAN VLANs in all source, intermediate, and destination network devices. If enabled, the VLAN Trunking Protocol (VTP) can propagate configuration of VLANs numbered 1 through 1024 as RSPAN VLANs. You must manually configure VLANs numbered higher than 1024 as RSPAN VLANs on all source, intermediate, and destination network devices.

•If you enable VTP and VTP pruning, RSPAN traffic is pruned in the trunks to prevent the unwanted flooding of RSPAN traffic across the network.

•RSPAN VLANs can be used only for RSPAN traffic.

•Do not configure a VLAN used to carry management traffic as an RSPAN VLAN.

•Do not assign access ports to RSPAN VLANs. RSPAN puts access ports in an RSPAN VLAN into the suspended state.

•Do not configure any ports in an RSPAN VLAN except trunk ports selected to carry RSPAN traffic.

•MAC address learning is disabled in the RSPAN VLAN.

•You can use output access control lists (ACLs) on the RSPAN VLAN in the RSPAN source switch to filter the traffic sent to an RSPAN destination.

•RSPAN does not support BPDU monitoring.

•Do not configure RSPAN VLANs as sources in VSPAN sessions.

•You can configure any VLAN as an RSPAN VLAN as long as all participating network devices support configuration of RSPAN VLANs and you use the same RSPAN VLAN for each RSPAN session in all participating network devices.

ERSPAN Guidelines and Restrictions

These are ERSPAN guidelines and restrictions:

•A WS-SUP720 (a Supervisor Engine 720 manufactured with a PFC3A) can only support ERSPAN if it has hardware version 3.2 or higher. Enter the show module version | include WS-SUP720-BASE command to display the hardware version. For example:

Router# show module version | include WS-SUP720-BASE 

 7    2  WS-SUP720-BASE     SAD075301SZ Hw :3.2

•For ERSPAN packets, the "protocol type" field value in the GRE header is 0x88BE.

•The payload of a Layer 3 ERSPAN packet is a copied Layer 2 Ethernet frame, excluding any ISL or 802.1Q tags.

•ERSPAN adds a 50-byte header to each copied Layer 2 Ethernet frame and replaces the 4-byte cyclic redundancy check (CRC) trailer.

•ERSPAN supports jumbo frames that contain Layer 3 packets of up to 9,202 bytes. If the length of the copied Layer 2 Ethernet frame is greater than 9,170 (9,152-byte Layer 3 packet), ERSPAN truncates the copied Layer 2 Ethernet frame to create a 9,202-byte ERSPAN Layer 3 packet.

Note The Layer 3 IP header in truncated packets retains the nontruncated Layer 3 packet size. The length consistency check between the Layer 2 frame and the Layer 3 packet on ERSPAN destinations that are 6500 switches drops truncated ERSPAN packets unless you configure the no mls verify ip length consistent global configuration command on the ERSPAN destination 6500 switch.

•Regardless of any configured MTU size, ERSPAN creates Layer 3 packets that can be as long as 9,202 bytes. ERSPAN traffic might be dropped by any interface in the network that enforces an MTU size smaller than 9,202 bytes.

•With the default MTU size (1,500 bytes), if the length of the copied Layer 2 Ethernet frame is greater than 1,468 bytes (1,450-byte Layer 3 packet), the ERSPAN traffic is dropped by any interface in the network that enforces the 1,500-byte MTU size.

Note The mtu interface command and the system jumbomtu command (see the "Configuring Jumbo Frame Support" section) set the maximum Layer 3 packet size (default is 1,500 bytes, maximum is 9,216 bytes).

•All participating switches must be connected at Layer 3 and the network path must support the size of the ERSPAN traffic.

•ERSPAN does not support packet fragmentation. The "do not fragment" bit is set in the IP header of ERSPAN packets. ERSPAN destination sessions cannot reassemble fragmented ERSPAN packets.

•ERSPAN traffic is subject to the traffic load conditions of the network. You can set the ERSPAN packet IP precedence or DSCP value to prioritize ERSPAN traffic for QoS.

•The only supported destination for ERSPAN traffic is an ERSPAN destination session on a PFC3.

•All ERSPAN source sessions on a switch must use the same origin IP address, configured with the origin ip address command (see the "Configuring ERSPAN Source Sessions" section).

•All ERSPAN destination sessions on a switch must use the same IP address on the same destination interface. You enter the destination interface IP address with the ip address command (see the "Configuring ERSPAN Destination Sessions" section).

•The ERSPAN source session's destination IP address, which must be configured on an interface on the destination switch, is the source of traffic that an ERSPAN destination session sends to the destinations. You configure the same address in both the source and destination sessions with the ip address command.

•The ERSPAN ID differentiates the ERSPAN traffic arriving at the same destination IP address from various different ERSPAN source sessions.

Distributed Egress SPAN Mode Guidelines and Restrictions

These are distributed egress SPAN mode guidelines and restrictions:

•These switching modules disable distributed egress SPAN mode:

–WS-X6502-10GE

–WS-X6816-GBIC

–WS-X6516-GBIC

–WS-X6516-GE-TX

–WS-X6524-100FX-MM

–WS-X6548-RJ-45

–WS-X6548-RJ-21

With any of these switching modules installed, the egress SPAN mode is centralized.

Enter the show monitor session egress replication-mode | include Operational|slot command to display any switching modules that disable distributed egress SPAN mode. If there are no modules installed that disable distributed egress SPAN mode, the command displays only the egress SPAN operational mode.

•Some switching modules have ASICs that do not support distributed egress SPAN mode for ERSPAN sources.

Enter the show monitor session egress replication-mode | include Distributed.*Distributed.*Centralized command to display the slot number of any switching modules that do not support distributed egress SPAN mode for ERSPAN sources.

Enter the show asic-version slot slot_number command to display the versions of the ASICs on the switching module in the slot where distributed egress SPAN mode is not supported for ERSPAN sources.

Hyperion ASIC revision levels 5.0 and higher and all versions of the Metropolis ASIC support distributed egress SPAN mode for ERSPAN sources. Switching modules with Hyperion ASIC revision levels lower than 5.0 do not support distributed egress SPAN mode for ERSPAN sources.

Configuring Local SPAN, RSPAN, and ERSPAN

These sections describe how to configure local SPAN, RSPAN, and ERSPAN:

•Local SPAN, RSPAN, and ERSPAN Default Configuration

•Configuring a Destination as an Unconditional Trunk (Optional)

•Configuring Destination Trunk VLAN Filtering (Optional)

•Configuring Destination Port Permit Lists (Optional)

•Configuring the Egress SPAN Mode (Optional)

•Configuring Local SPAN

•Configuring RSPAN

•Configuring ERSPAN

•Configuring Source VLAN Filtering in Global Configuration Mode

•Verifying the Configuration

•Configuration Examples

Local SPAN, RSPAN, and ERSPAN Default Configuration

This section describes the local SPAN, RSPAN, and ERSPAN default configuration:

Configuring a Destination as an Unconditional Trunk (Optional)

To tag the monitored traffic as it leaves a destination, configure the destination as a trunk before you configure it as a destination.

To configure the destination as a trunk, perform this task:

This example shows how to configure a port as an unconditional IEEE 802.1Q trunk:

Router(config)# interface fastethernet 5/12 

Router(config-if)# switchport 

Router(config-if)# switchport trunk encapsulation dot1q 

Router(config-if)# switchport mode trunk 

Note Releases earlier than Release 12.2(33)SXH required you to enter the switchport nonegotiate command when you configured a destination port as an unconditional trunk. This requirement has been removed in Release 12.2(33)SXH and later releases.

Configuring Destination Trunk VLAN Filtering (Optional)

Note•In addition to filtering VLANs on a trunk, you can also apply the allowed VLAN list to access ports.

•Destination trunk VLAN filtering is applied at the destination. Destination trunk VLAN filtering does not reduce the amount of traffic being sent from the SPAN sources to the SPAN destinations.

When a destination is a trunk, you can use the list of VLANs allowed on the trunk to filter the traffic transmitted from the destination. (CSCeb01318)

Destination trunk VLAN filtering removes the restriction that, within a SPAN session, all destinations receive all the traffic from all the sources. Destination trunk VLAN filtering allows you to select, on a per-VLAN basis, the traffic that is transmitted from each destination trunk to the network analyzer.

To configure destination trunk VLAN filtering on a destination trunk, perform this task:

When configuring the list of VLANs allowed on a destination trunk port, note the following information:

•The vlan parameter is either a single VLAN number from 1 through 4094, or a range of VLANs described by two VLAN numbers, the lesser one first, separated by a dash. Do not enter any spaces between comma-separated vlan parameters or in dash-specified ranges.

•All VLANs are allowed by default.

•To remove all VLANs from the allowed list, enter the switchport trunk allowed vlan none command.

•To add VLANs to the allowed list, enter the switchport trunk allowed vlan add command.

•You can modify the allowed VLAN list without removing the SPAN configuration.

This example shows the configuration of a local SPAN session that has several VLANs as sources and several trunk ports as destinations, with destination trunk VLAN filtering that filters the SPAN traffic so that each destination trunk port transmits the traffic from one VLAN:

interface GigabitEthernet1/1

description SPAN destination interface for VLAN 10

no ip address

switchport

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 10

switchport mode trunk

switchport nonegotiate

!

interface GigabitEthernet1/2

description SPAN destination interface for VLAN 11

no ip address

switchport

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 11

switchport mode trunk

switchport nonegotiate

!

interface GigabitEthernet1/3

description SPAN destination interface for VLAN 12

no ip address

switchport

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 12

switchport mode trunk

switchport nonegotiate

!

interface GigabitEthernet1/4

description SPAN destination interface for VLAN 13

no ip address

switchport

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 13

switchport mode trunk

switchport nonegotiate

!

monitor session 1 source vlan 10 - 13

monitor session 1 destination interface Gi1/1 - 4

Configuring Destination Port Permit Lists (Optional)

To prevent accidental configuration of ports as destinations, you can create a permit list of the ports that are valid for use as destinations. With a destination port permit list configured, you can only configure the ports in the permit list as destinations.

To configure a destination port permit list, perform this task:

This example shows how to configure a destination port permit list that includes Gigabit Ethernet ports 5/1 through 5/4 and 6/1:

Router# configure terminal 

Router(config)# monitor permit-list 

Router(config)# monitor permit-list destination interface gigabitethernet 5/1-4, 
gigabitethernet 6/1 

This example shows how to verify the configuration:

Router(config)# do show monitor permit-list 

 SPAN Permit-list      :Admin Enabled

 Permit-list ports     :Gi5/1-4,Gi6/1

Configuring the Egress SPAN Mode (Optional)

With Release 12.2(33)SXH, Release 12.2(33)SXH1, and Release 12.2(33)SXH2, distributed egress SPAN mode is the default if there are no switching modules installed that disable it.

With Release 12.2(33)SXH2a and later releases, centralized egress SPAN mode is the default.

See the "Distributed Egress SPAN Mode Guidelines and Restrictions" section for information about switching modules that support distributed egress SPAN mode.

With Release 12.2(33)SXH2a and later releases, to configure the egress SPAN mode, perform this task:

This example shows how to enable distributed egress SPAN mode:

Router# configure terminal 

Router(config)# monitor session egress replication-mode distributed 

Router(config)# end 

With Release 12.2(33)SXH, Release 12.2(33)SXH1, and Release 12.2(33)SXH2, to configure the egress SPAN mode, perform this task:

This example shows how to disable distributed egress SPAN mode:

Router# configure terminal 

Router(config)# monitor session egress replication-mode centralized 

Router(config)# end 

This example shows how to display the configured egress SPAN mode:

Router# show monitor session egress replication-mode | include Configured 

Configured mode  : Centralized

Configuring Local SPAN

These sections describe how to configure local SPAN sessions:

•Configuring Local SPAN (SPAN Configuration Mode)

•Configuring Local SPAN (Global Configuration Mode)

Configuring Local SPAN (SPAN Configuration Mode)

Note To tag the monitored traffic as it leaves a destination, you must configure the destination to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination as an Unconditional Trunk (Optional)" section).

To configure a local SPAN session in SPAN configuration mode, perform this task:

When configuring monitor sessions, note the following information:

•session_description can be up to 240 characters and cannot contain special characters; with Release 12.2(33)SXH and later releases, the description can contain spaces.

Note You can enter 240 characters after the description command.

•local_span_session_number can range from 1 to 80.

•cpu rp is the route processor (RP).

•cpu sp is the switch processor (SP).

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Destination port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•Enter the ingress keyword to configure destinations to receive traffic from attached devices.

•Enter the learning keyword to enable MAC address learning from the destinations, which allows the switch to transmit traffic that is addressed to devices attached to the destinations.

When configuring destinations with the ingress and learning keywords, note the following:

–Configure the destinations for Layer 2 switching. See the "Configuring LAN Interfaces for Layer 2 Switching" section.

–If the destination is a trunk and the attached device transmits tagged traffic back to the switch, you can use either ISL or 802.1Q trunking.

–If the destination is a trunk and the attached device transmits untagged traffic back to the switch, use 802.1Q trunking with the native VLAN configured to accept the traffic from the attached device.

–Do not configure the destinations with Layer 3 addresses. Use a VLAN interface to route traffic to and from devices attached to destinations.

–Destinations are held in the down state. To route the traffic to and from attached devices, configure an additional active Layer 2 port in the VLAN to keep the VLAN interface up.

This example shows how to configure session 1 to monitor ingress traffic from Gigabit Ethernet port 1/1 and configure Gigabit Ethernet port 1/2 as the destination:

Router(config)# monitor session 1 type local 

Router(config-mon-local)# source interface gigabitethernet 1/1 rx 

Router(config-mon-local)# destination interface gigabitethernet 1/2 

For additional examples, see the "Configuration Examples" section.

Configuring Local SPAN (Global Configuration Mode)

Note•To tag the monitored traffic as it leaves a destination, you must configure the destination to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination as an Unconditional Trunk (Optional)" section).

•You can configure up to two local SPAN sessions in global configuration mode.

•You can use SPAN configuration mode for all SPAN configuration tasks.

•You must use SPAN configuration mode to configure the supported maximum number of SPAN sessions.

Local SPAN does not use separate source and destination sessions. To configure a local SPAN session, configure local SPAN sources and destinations with the same session number. To configure a local SPAN session, perform this task:

When configuring local SPAN sessions, note the following information:

•local_span_session_number can range from 1 to 80.

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Destination port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•Enter the ingress keyword to configure destinations to receive traffic from attached devices.

•Enter the learning keyword to enable MAC address learning from the destinations, which allows the switch to transmit traffic that is addressed to devices attached to the destinations.

When configuring destinations with the ingress and learning keywords, note the following:

–Configure the destinations for Layer 2 switching. See the "Configuring LAN Interfaces for Layer 2 Switching" section.

–If the destination is a trunk and the attached device transmits tagged traffic back to the switch, you can use either ISL or 802.1Q trunking.

–If the destination is a trunk and the attached device transmits untagged traffic back to the switch, use 802.1Q trunking with the native VLAN configured to accept the traffic from the attached device.

–Do not configure the destinations with Layer 3 addresses. Use a VLAN interface to route traffic to and from devices attached to destinations.

–Destinations are held in the down state. To route the traffic to and from attached devices, configure an additional active Layer 2 port in the VLAN to keep the VLAN interface up.

This example shows how to configure Fast Ethernet port 5/1 as a bidirectional source for session 1:

Router(config)# monitor session 1 source interface fastethernet 5/1 

This example shows how to configure Fast Ethernet port 5/48 as the destination for SPAN session 1:

Router(config)# monitor session 1 destination interface fastethernet 5/48 

For additional examples, see the "Configuration Examples" section.

Configuring RSPAN

RSPAN uses a source session on one switch and a destination session on a different switch. These sections describe how to configure RSPAN sessions:

•Configuring RSPAN VLANs

•Configuring RSPAN Sessions (SPAN Configuration Mode)

•Configuring RSPAN Sessions (Global Configuration Mode)

Configuring RSPAN VLANs

To configure a VLAN as an RSPAN VLAN, perform this task:

Configuring RSPAN Sessions (SPAN Configuration Mode)

These sections describe how to configure RSPAN sessions in SPAN configuration mode:

•Configuring RSPAN Source Sessions in SPAN Configuration Mode

•Configuring RSPAN Destination Sessions in SPAN Configuration Mode

Configuring RSPAN Source Sessions in SPAN Configuration Mode

To configure an RSPAN source session in SPAN configuration mode, perform this task:

When configuring RSPAN source sessions, note the following information:

•session_description can be up to 240 characters and cannot contain special characters; with Release 12.2(33)SXH and later releases, the description can contain spaces.

Note You can enter 240 characters after the description command.

•RSPAN_source_span_session_number can range from 1 to 80.

•cpu rp is the route processor (RP).

•cpu sp is the switch processor (SP).

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•See the "Configuring RSPAN VLANs" section for information about the RSPAN VLAN ID.

This example shows how to configure session 1 to monitor bidirectional traffic from Gigabit Ethernet port 1/1:

Router(config)# monitor session 1 type rspan-source 

Router(config-mon-rspan-src)# source interface gigabitethernet 1/1 

Router(config-mon-rspan-src)# destination remote vlan 2 

For additional examples, see the "Configuration Examples" section.

Configuring RSPAN Destination Sessions in SPAN Configuration Mode

Note•To tag the monitored traffic, you must configure the port to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination as an Unconditional Trunk (Optional)" section).

•You can configure an RSPAN destination session on the RSPAN source session switch to monitor RSPAN traffic locally.

To configure an RSPAN destination session, perform this task:

When configuring RSPAN destination sessions, note the following information:

•RSPAN_destination_span_session_number can range from 1 to 80.

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Destination port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•Enter the ingress keyword to configure destinations to receive traffic from attached devices.

•Enter the learning keyword to enable MAC address learning from the destinations, which allows the switch to transmit traffic that is addressed to devices attached to the destinations.

When configuring destinations with the ingress and learning keywords, note the following:

–Configure the destinations for Layer 2 switching. See the "Configuring LAN Interfaces for Layer 2 Switching" section.

–If the destination is a trunk and the attached device transmits tagged traffic back to the switch, you can use either ISL or 802.1Q trunking.

–If the destination is a trunk and the attached device transmits untagged traffic back to the switch, use 802.1Q trunking with the native VLAN configured to accept the traffic from the attached device.

–Do not configure the destinations with Layer 3 addresses. Use a VLAN interface to route traffic to and from devices attached to destinations.

–Destinations are held in the down state. To route the traffic to and from attached devices, configure an additional active Layer 2 port in the VLAN to keep the VLAN interface up.

•The no shutdown command and shutdown commands are not supported for RSPAN destination sessions.

This example shows how to configure RSPAN VLAN 2 as the source for session 1 and Gigabit Ethernet port 1/2 as the destination:

Router(config)# monitor session 1 type rspan-destination 

Router(config-rspan-dst)# source remote vlan 2 

Router(config-rspan-dst)# destination interface gigabitethernet 1/2 

For additional examples, see the "Configuration Examples" section.

Configuring RSPAN Sessions (Global Configuration Mode)

These sections describe how to configure RSPAN sessions in global configuration mode:

•Configuring RSPAN Source Sessions in Global Configuration Mode

•Configuring RSPAN Destination Sessions in Global Configuration Mode

Configuring RSPAN Source Sessions in Global Configuration Mode

To configure an RSPAN source session in global configuration mode, perform this task:

When configuring RSPAN source sessions, note the following information:

•To configure RSPAN VLANs, see the "Configuring RSPAN VLANs" section.

•RSPAN_source_span_session_number can range from 1 to 80.

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•See the "Configuring RSPAN VLANs" section for information about the RSPAN VLAN ID.

This example shows how to configure Fast Ethernet port 5/2 as the source for session 2:

Router(config)# monitor session 2 source interface fastethernet 5/2 

This example shows how to configure RSPAN VLAN 200 as the destination for session 2:

Router(config)# monitor session 2 destination remote vlan 200 

For additional examples, see the "Configuration Examples" section.

Configuring RSPAN Destination Sessions in Global Configuration Mode

Note•To tag the monitored traffic, you must configure the port to trunk unconditionally before you configure it as a destination (see the "Configuring a Destination as an Unconditional Trunk (Optional)" section).

•You can configure an RSPAN destination session on the RSPAN source session switch to monitor RSPAN traffic locally.

To configure an RSPAN destination session in global configuration mode, perform this task:

When configuring monitor sessions, note the following information:

•RSPAN_destination_span_session_number can range from 1 to 80.

•See the "Configuring RSPAN VLANs" section for information about the RSPAN VLAN ID.

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Destination port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•Enter the ingress keyword to configure destinations to receive traffic from attached devices.

•Enter the learning keyword to enable MAC address learning from the destinations, which allows the switch to transmit traffic that is addressed to devices attached to the destinations.

When configuring destinations with the ingress and learning keywords, note the following:

–Configure the destinations for Layer 2 switching. See the "Configuring LAN Interfaces for Layer 2 Switching" section.

–If the destination is a trunk and the attached device transmits tagged traffic back to the switch, you can use either ISL or 802.1Q trunking.

–If the destination is a trunk and the attached device transmits untagged traffic back to the switch, use 802.1Q trunking with the native VLAN configured to accept the traffic from the attached device.

–Do not configure the destinations with Layer 3 addresses. Use a VLAN interface to route traffic to and from devices attached to destinations.

–Destinations are held in the down state. To route the traffic to and from attached devices, configure an additional active Layer 2 port in the VLAN to keep the VLAN interface up.

This example shows how to configure RSPAN VLAN 200 as the source for session 3:

Router(config)# monitor session 3 source remote vlan 200 

This example shows how to configure Fast Ethernet port 5/47 as the destination for session 3:

Router(config)# monitor session 3 destination interface fastethernet 5/47 

For additional examples, see the "Configuration Examples" section.

Configuring ERSPAN

ERSPAN uses separate source and destination sessions. You configure the source and destination sessions on different switches. These sections describe how to configure ERSPAN sessions:

•Configuring ERSPAN Source Sessions

•Configuring ERSPAN Destination Sessions

Configuring ERSPAN Source Sessions

To configure an ERSPAN source session, perform this task:

When configuring monitor sessions, note the following information:

•session_description can be up to 240 characters and cannot contain special characters; with Release 12.2(33)SXH and later releases, the description can contain spaces.

Note You can enter 240 characters after the description command.

•ERSPAN_source_span_session_number can range from 1 to 80.

•cpu rp is the route processor (RP).

•cpu sp is the switch processor (SP).

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

•ERSPAN_flow_id can range from 1 to 1023.

•All ERSPAN source sessions on a switch must use the same source IP address. Enter the origin ip address ip_address force command to change the origin IP address configured in all ERSPAN source sessions on the switch.

•ttl_value can range from 1 to 255.

•ipp_value can range from 0 to 7.

•dscp_value can range from 0 to 63.

This example shows how to configure session 3 to monitor bidirectional traffic from Gigabit Ethernet port 4/1:

Router(config)# monitor session 3 type erspan-source 

Router(config-mon-erspan-src)# source interface gigabitethernet 4/1 

Router(config-mon-erspan-src)# destination 

Router(config-mon-erspan-src-dst)# ip address 10.1.1.1 

Router(config-mon-erspan-src-dst)# origin ip address 20.1.1.1 

Router(config-mon-erspan-src-dst)# erspan-id 101 

For additional examples, see the "Configuration Examples" section.

Configuring ERSPAN Destination Sessions

Note You cannot monitor ERSPAN traffic locally.

To configure an ERSPAN destination session, perform this task:

When configuring monitor sessions, note the following information:

•ERSPAN_destination_span_session_number can range from 1 to 80.

•single_interface is as follows:

–interface type slot/port; type is fastethernet, gigabitethernet, or tengigabitethernet.

–interface port-channel number

Note Destination port channel interfaces must be configured with the channel-group group_num mode on command and the no channel-protocol command. See the "Configuring EtherChannels" section.

•interface_list is single_interface , single_interface , single_interface ...

Note In lists, you must enter a space before and after the comma. In ranges, you must enter a space before and after the dash.

•interface_range is interface type slot/first_port - last_port.

•mixed_interface_list is, in any order, single_interface , interface_range , ...

•All ERSPAN destination sessions on a switch must use the same IP address on the same destination interface. Enter the ip address ip_address force command to change the IP address configured in all ERSPAN destination sessions on the switch.

Note You must also change all ERSPAN source session destination IP addresses (see the "Configuring ERSPAN Source Sessions" section, Step 7).

•ERSPAN_flow_id can range from 1 to 1023.

•Enter the ingress keyword to configure destinations to receive traffic from attached devices.

•Enter the learning keyword to enable MAC address learning from the destinations, which allows the switch to transmit traffic that is addressed to devices attached to the destinations.

When configuring destinations with the ingress and learning keywords, note the following:

–Configure the destinations for Layer 2 switching. See the "Configuring LAN Interfaces for Layer 2 Switching" section.

–If the destination is a trunk and the attached device transmits tagged traffic back to the switch, you can use either ISL or 802.1Q trunking.

–If the destination is a trunk and the attached device transmits untagged traffic back to the switch, use 802.1Q trunking with the native VLAN configured to accept the traffic from the attached device.

–Do not configure the destinations with Layer 3 addresses. Use a VLAN interface to route traffic to and from devices attached to destinations.

–Destinations are held in the down state. To route the traffic to and from attached devices, configure an additional active Layer 2 port in the VLAN to keep the VLAN interface up.

This example shows how to configure an ERSPAN destination session to send ERSPAN ID 101 traffic arriving at IP address 10.1.1.1 to Gigabit Ethernet port 2/1:

Router(config)# monitor session 3 type erspan-destination 

Router(config-erspan-dst)# destination interface gigabitethernet 2/1 

Router(config-erspan-dst)# source 

Router(config-erspan-dst-src)# ip address 10.1.1.1 

Router(config-erspan-dst-src)# erspan-id 101 

For additional examples, see the "Configuration Examples" section.

Configuring Source VLAN Filtering in Global Configuration Mode

Note•To configure source VLAN filtering in SPAN configuration mode, see the following sections:

–Configuring Local SPAN (SPAN Configuration Mode)

–Configuring RSPAN Source Sessions in SPAN Configuration Mode

–Configuring ERSPAN

•Source VLAN filtering reduces the amount of traffic that is sent from SPAN sources to SPAN destinations.

Source VLAN filtering monitors specific VLANs when the source is a trunk port.

To configure source VLAN filtering when the local SPAN or RSPAN source is a trunk port, perform this task:

When configuring source VLAN filtering, note the following information:

•single_vlan is the ID number of a single VLAN.

•vlan_list is single_vlan , single_vlan , single_vlan ...

•vlan_range is first_vlan_ID - last_vlan_ID.

•mixed_vlan_list is, in any order, single_vlan , vlan_range , ...

This example shows how to monitor VLANs 1 through 5 and VLAN 9 when the source is a trunk port:

Router(config)# monitor session 2 filter vlan 1 - 5 , 9 

Verifying the Configuration

To verify the configuration, enter the show monitor session command.

This example shows how to verify the configuration of session 2:

Router# show monitor session 2

Session 2

------------

Type : Remote Source Session

Source Ports:

    RX Only:       Fa3/1

Dest RSPAN VLAN:   901

Router#

This example shows how to display the full details of session 2:

Router# show monitor session 2 detail 

Session 2

------------

Type : Remote Source Session

Source Ports:

    RX Only:       Fa1/1-3

    TX Only:       None

    Both:          None

Source VLANs:

    RX Only:       None

    TX Only:       None

    Both:          None

Source RSPAN VLAN: None

Destination Ports: None

Filter VLANs:      None

Dest RSPAN VLAN:   901

Configuration Examples

This example shows the configuration of RSPAN source session 2:

Router(config)# monitor session 2 source interface fastethernet1/1 - 3 rx 

Router(config)# monitor session 2 destination remote vlan 901 

This example shows how to clear the configuration for sessions 1 and 2:

Router(config)# no monitor session range 1-2 

This example shows the configuration of an RSPAN source session with multiple sources:

Router(config)# monitor session 2 source interface fastethernet 5/15 , 7/3 rx 

Router(config)# monitor session 2 source interface gigabitethernet 1/2 tx 

Router(config)# monitor session 2 source interface port-channel 102 

Router(config)# monitor session 2 source filter vlan 2 - 3 

Router(config)# monitor session 2 destination remote vlan 901 

This example shows how to remove sources for a session:

Router(config)# no monitor session 2 source interface fastethernet 5/15 , 7/3 

This example shows how to remove options for sources for a session:

Router(config)# no monitor session 2 source interface gigabitethernet 1/2 

Router(config)# no monitor session 2 source interface port-channel 102 tx 

This example shows how to remove source VLAN filtering for a session:

Router(config)# no monitor session 2 filter vlan 3 

This example shows the configuration of RSPAN destination session 8:

Router(config)# monitor session 8 source remote vlan 901 

Router(config)# monitor session 8 destination interface fastethernet 1/2 , 2/3 

This example shows the configuration of ERSPAN source session 12:

monitor session 12 type erspan-source

 description SOURCE_SESSION_FOR_VRF_GRAY

 source interface Gi8/48 rx

 destination

  erspan-id 120

  ip address 10.8.1.2

  origin ip address 32.1.1.1

  vrf gray

This example shows the configuration of ERSPAN destination session 12:

monitor session 12 type erspan-destination

 description DEST_SESSION_FOR_VRF_GRAY

 destination interface Gi4/48

 source

  erspan-id 120

  ip address 10.8.1.2

  vrf gray

This example shows the configuration of ERSPAN source session 13:

monitor session 13 type erspan-source

 source interface Gi6/1 tx

 destination

  erspan-id 130

  ip address 10.11.1.1

  origin ip address 32.1.1.1

This example shows the configuration of ERSPAN destination session 13:

monitor session 13 type erspan-destination

 destination interface Gi6/1

 source

  erspan-id 130

  ip address 10.11.1.1

Tip For additional information about Cisco Catalyst 6500 Series Switches (including configuration examples and troubleshooting information), see the documents listed on this page:

http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html

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