Perform this task to configure Path Preference Hierarchy feature on a hub.
domain default
vrf green
master hub
source-interface Loopback1
site-prefixes prefix-list HUBPFX
class HEIRARCHICAL sequence 100
match dscp ef policy custom
priority 1 loss threshold 10
path-preference ISP1 ISP2 fallback ISP3 next-fallback blackhole
The following is a sample output on a device that displays the route change reason and history. In this example, the traffic
class jumps from next-fallback service provider to primary service provider, when the fallback is unavailable.
Dst-Site-Prefix: 100.30.0.0/16 DSCP: ef [46] Traffic class id:2
Clock Time: 12:57:15 (PST) 03/30/2015
TC Learned: 00:22:14 ago
Present State: CONTROLLED
Current Performance Status: in-policy
Current Service Provider: ISP2 path-id:2 since 00:03:28
Previous Service Provider: ISP3 pfr-label: 0:0 | 0:7 [0x7] for 180 sec
(A fallback/next-fallback provider. Primary provider will be re-evaluated 00:02:34 later)
BW Used: 3 Kbps
Present WAN interface: Tunnel20 in Border 100.10.2.1
Present Channel (primary): 46 ISP2 pfr-label:0:0 | 0:2 [0x2]
Backup Channel: 42 ISP3 pfr-label:0:0 | 0:7 [0x7]
Destination Site ID bitmap: 0
Destination Site ID: 100.30.1.1
Class-Sequence in use: 10
Class Name: BUSINESS using policy User-defined
priority 2 packet-loss-rate threshold 10.0 percent
priority 2 byte-loss-rate threshold 10.0 percent
BW Updated: 00:00:14 ago
Reason for Latest Route Change: next-fallback to Higher Path Preference
Route Change History:
Date and Time Previous Exit Current Exit Reason
1: 12:53:47 (PST) 03/30/2015 ISP3/100.10.1.1/Tu30 (Ch:42) ISP2/100.10.2.1/Tu20 (Ch:46) next-fallback to Higher Path Preference
2: 12:50:47 (PST) 03/30/2015 None/0.0.0.0/None (Ch:0) ISP3/100.10.1.1/Tu30 (Ch:42) Uncontrolled to Controlled Transition
3: 12:50:15 (PST) 03/30/2015 ISP3/100.10.1.1/Tu30 (Ch:42) None/0.0.0.0/None (Ch:0) No Channels Available
4: 12:48:14 (PST) 03/30/2015 ISP2/100.10.4.1/Tu20 (Ch:43) ISP3/100.10.1.1/Tu30 (Ch:42) Exit down
5: 12:47:57 (PST) 03/30/2015 ISP2/100.10.2.1/Tu20 (Ch:46) ISP2/100.10.4.1/Tu20 (Ch:43) Exit down
In the following example, continuation of the above example, the traffic class is now controlled by primary service provider.
Route Change History:
Date and Time Previous Exit Current Exit Reason
1: 12:59:49 (PST) 03/30/2015 ISP2/100.10.2.1/Tu20 (Ch:46) ISP1/100.10.1.1/Tu10 (Ch:41) Backup to Primary path preference transition
2: 12:53:47 (PST) 03/30/2015 ISP3/100.10.1.1/Tu30 (Ch:42) ISP2/100.10.2.1/Tu20 (Ch:46) next-fallback to Higher Path Preference
3: 12:50:47 (PST) 03/30/2015 None/0.0.0.0/None (Ch:0) ISP3/100.10.1.1/Tu30 (Ch:42) Uncontrolled to Controlled Transition
4: 12:50:15 (PST) 03/30/2015 ISP3/100.10.1.1/Tu30 (Ch:42) None/0.0.0.0/None (Ch:0) No Channels Available
5: 12:48:14 (PST) 03/30/2015 ISP2/100.10.4.1/Tu20 (Ch:43) ISP3/100.10.1.1/Tu30 (Ch:42) Exit down
In the following example, continuation of the above example, the traffic class is discarded since the packet has reached a
blackhole.
Route Change History:
Date and Time Previous Exit Current Exit Reason
1: 12:50:15 (PST) 03/30/2015 ISP3/100.10.1.1/Tu30 (Ch:42) None/0.0.0.0/None (Ch:0) No Channels Available
2: 12:48:14 (PST) 03/30/2015 ISP2/100.10.4.1/Tu20 (Ch:43) ISP3/100.10.1.1/Tu30 (Ch:42) Exit down
3: 12:47:57 (PST) 03/30/2015 ISP2/100.10.2.1/Tu20 (Ch:46) ISP2/100.10.4.1/Tu20 (Ch:43) Exit down
4: 12:44:42 (PST) 03/30/2015 ISP1/100.10.1.1/Tu10 (Ch:41) ISP2/100.10.2.1/Tu20 (Ch:46) Exit down
5: 12:44:13 (PST) 03/30/2015 ISP1/100.10.3.1/Tu10 (Ch:44) ISP1/100.10.1.1/Tu10 (Ch:41) Exit down