> My working theory is that syslogging started blocking for some
> reason, thus stalling anything that wanted to log anything (which
> stalls named, anything with tcpwrappers, mail, news, etc).
I have seen this behaviour before several times. However, the code-base for
syslogd on RH has changed at least several times since then, so who knows if
it's the same bug now as then. The applications block when trying to write
to the syslog pipe, so calls to syslog() never return and programs hang.
> I think the discussion was whether the syslog libc function should
> open /dev/log in blocking or non-blocking mode. If it opens it in
> blocking mode and syslogd dies, then all apps will block on writing
> to /dev/log. Does this ring a bell with anyone?
On the grounds that things start working again when you kill syslogd, this
doesn't sound correct. It's syslogd which goes tits up and which causes the
write processes to block.
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