On 8/4/05, poncenby <[EMAIL PROTECTED]> wrote:
> I remember asking how to stop syslogd opening udp port 514 a while ago
> and never doing anything about it, here goes again...

Sure, syslogd opens UDP/514, but unless you use the '-u' flag the very
next thing it does is call shutdown(), which prevents inbound traffic on
the "listening" port:
     http://www.bsdforums.org/forums/showthread.php?t=33250


> reading the man page doesn't really answer why there is program
> listening on udp 514, seeing as I haven't passed syslogd the -u switch
> 
> -u      Select the historical ``insecure'' mode, in which syslogd will
>          accept input from the UDP port.  Some software wants this, but
>          you can be subjected to a variety of attacks over the network,
>          including attackers remotely filling logs.
> 
> can anyone point me in the right direction so this annoying behaviour stops.

I agree, it is (mildly) annoying.

The syslog daemon must bind UDP/514 even without the '-u' flag because
syslogd uses this socket as the source port if/when you configure a
remote log destination in /etc/syslogd.conf.

FreeBSD has the '-s -s' flag which prevents the daemon from binding the
port at all, but this is not necessary as a security enhancement, forcing
syslogd not to bind the port is purely cosmetic, makes your netstat
output shorter by one line.

Kevin Kadow

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