[LU-18812] lnet: restrict IP addresses that socklnd listens on

• Type: Improvement
• Resolution: Unresolved
• Priority: Minor
• Affects Version/s: Lustre 2.17.0
• Labels: easy lnet
• Severity: 3
• Assignee: Serguei Smirnov
• Reporter: Andreas Dilger

Description

The socklnd acceptor listens for new connections on port 988 by default on all IP addresses:

# netstat -an | grep -w 988
tcp        0      0 0.0.0.0:988             0.0.0.0:*               LISTEN     
tcp        0      0 192.168.20.159:1022     192.168.20.1:988        ESTABLISHED
tcp        0      0 192.168.20.159:1023     192.168.20.1:988        ESTABLISHED
tcp        0      0 192.168.20.159:1021     192.168.20.1:988        ESTABLISHED

In some scenarios, it is desirable to not listen for connections on all addresses. It should be possible to limit the acceptor to listen only on specific addresses.