質問
自分の ESA がオープン リレーとして使用されることを防ぐにはどうしますか。
ESAがオープンリレーとして使用されないようにするには、パブリックリスナーの受信者アクセステーブル(RAT)で受信者ドメインを指定していること、および「ALL」エントリが「Reject」に設定されていることを確認します。RATエントリは、GUIのMail Policiesタブから追加できます。CLIを使用してドメイン「example.com」をRATに追加する方法を示す例を次に示します。
mail.example.com> listenerconfig
Currently configured listeners:
1. InboundMail (on PublicNet, 172.19.1.80) SMTP TCP Port 25 Public
2. OutboundMail (on PrivateNet, 172.19.2.80) SMTP TCP Port 25 Private
Choose the operation you want to perform:
- NEW - Create a new listener.
- EDIT - Modify a listener.
- DELETE - Remove a listener.
- SETUP - Change global settings.
[]> edit
Enter the name or number of the listener you wish to edit.
[]> 1
Name: InboundMail
Type: Public
Interface: PublicNet (172.19.1.80/24) TCP Port 25
Protocol: SMTP
Default Domain:
Max Concurrency: 1000 (TCP Queue: 50)
Domain Map: Disabled
TLS: No
SMTP Authentication: Disabled
Bounce Profile: Default
Use SenderBase For Reputation Filters and IP Profiling: Yes
Footer: None
LDAP: Off
Choose the operation you want to perform:
- NAME - Change the name of the listener.
- INTERFACE - Change the interface.
- LIMITS - Change the injection limits.
- SETUP - Configure general options.
- HOSTACCESS - Modify the Host Access Table.
- RCPTACCESS - Modify the Recipient Access Table.
- BOUNCECONFIG - Choose the bounce profile to use for messages injected on
this listener.
- MASQUERADE - Configure the Domain Masquerading Table.
- DOMAINMAP - Configure domain mappings.
[]> rcptaccess
Recipient Access Table
There are currently 1 recipients.
Default Access: REJECT<
Choose the operation you want to perform:
- NEW - Create a new entry.
- EDIT - Modify an entry.
- IMPORT - Import a table from a file.
- EXPORT - Export the table to a file.
[]> new
Enter the recipient address for this entry.
Hostnames such as "example.com" and "[1.2.3.4]" are allowed.
Partial hostnames such as ".example.com" are allowed.
Usernames such as "postmaster@" are allowed.
Full email addresses such as "joe@example.com" or "joe@[1.2.3.4]" are allowed.
Separate multiple addresses with commas.
[]> example.com
Select the action to apply to this address:
1. Accept
2. Reject
[1]>
Would you like to specify a custom SMTP response? [N]>
Would you like to bypass receiving control for this entry? [N]>
Recipient Access Table
There are currently 2 recipients.
Default Access: REJECT
Choose the operation you want to perform:
- NEW - Create a new entry.
- EDIT - Modify an entry.
- DELETE - Remove an entry.
- PRINT - Display all entries.
- IMPORT - Import a table from a file.
- EXPORT - Export the table to a file.
- CLEAR - Remove all entries.
[]> print
ironport.com ACCEPT
ALL REJECT
「ALL」エントリが「REJECT」に構成されていることに注意してください。このエントリにより、特に受入が構成されていないホストからのメッセージがシステムで拒否されます。