[syslog-ng] io.c: bind_inet_socket() bind failed Address already inuse

[Evan Rempel]

Balazs Scheidler wrote:
> On Wed, 2008-04-09 at 18:05 +0300, Lucky Y wrote:
>>>> We use syslog-ng 1.6.12 in RHEL4.
>>>> As part of our system testing we restart syslog-ng 150 times in a loop
>>>> along with other services in the server.
>>>>
>>>> syslog-ng fails to come up 3/4 times with the error :
>>>> "io.c: bind_inet_socket() bind failed 192.168.128.1:601
>>>> Address already in use".
>>> How do you restart syslog-ng? It takes some time to close sources/
>>> destinations and there is a chance that the new syslog-ng instance
>>> tries to bind to the same address the not-yet-stopped instance
>>> still uses.
>> Does syslog-ng use SO_REUSEADDR option ?
> 
> Of course.

Does syslog-ng close the socket *before* flushing its buffers and closing it's files?

Doing so would address this race condition (kill, start without waiting), but it
would introduce another race where the new syslog-ng would be opening files that
are not yet closed by the old syslog-ng.

The "restart" method used should ensure that the process is finished prior to starting another one.


-- 
Evan Rempel                erempel at uvic.ca
Senior Programmer Analyst        250.721.7691
Computing Services
University of Victoria