Debug messages logging network traffic only include the address of one peer
Even with -d 99
used on the command line, named
only logs lines
like:
28-Sep-2023 14:31:23.212 sending packet to 2001:503:ba3e::2:30#53
or:
28-Sep-2023 14:31:23.232 received packet from 2001:503:ba3e::2:30#53
However, network traffic is always sent from one socket to another. The currently available debug messages do not include the sender's address (first example) or the receiver's address (second example). As a result, just bumping up the log level is often not enough to diagnose certain issues and a network traffic sniffer has to be used in order to learn the details of the packets being exchanged.
This lack of detail sometimes also makes debugging system test issues
harder than it has to be. With multiple tests being run in parallel,
knowing the exact addresses and ports that were used by each running
named
instance is crucial for determining whether a test failure was
caused by an unexpected interaction between tests or not. (Such issues
happened more than once in the past, particularly when network code
and/or the system test framework were being worked on.)
Debug messages logging network traffic should be extended to include information about both sides of each communication channel.
While this issue is technically only tangential to #4344, having detailed network-level information available would greatly improve the benefits of the feature proposed here.