Logging category update, 8.3.x

[Pete Ehlke]

It's been a while since I've done any serious work with 8, so when a
friend came to me yesterday asking why update logging doesn't seem to
work, I spent some time looking at it.

Given this block:

logging {
        channel update_log {
                file "/tmp/update.log";
                print-time yes;
                print-category yes;
                };
        category update { update_log; };
};

8.3.4 does not create update.log at startup. If update.log is created
manually, and the server successfully processes an update, the update is
not logged.

If, however, I do this:

logging {
        channel update_log {
                file "/tmp/update.log";
                print-time yes;
                print-category yes;
                };
        category queries { update_log; };
};

then the server *does* create update.log at startup.

In http://www.menandmice.com/9000/9320_DNS_Corner_Q&A/93_Q&A_027.html
Cricket notes the well-known situation that *denied* updates go to
security, not update, but doesn't respond to the posters' report that
his update log file is not created. I'm seeing the same behaviour, with the
added problem that successful updates are not being logged even after I
manually create the file.

So, what's the skinny on category update in 8.3.x? I confess to being stumped.

Thanks.
-Pete