Freeradius 3.0.8 Can't create UNIX socket and Too many open files

[Alan DeKok]

On Apr 28, 2015, at 2:27 PM, Rygl Aleš <ales at rygl.net> wrote:
> I had to raise them because freeradius daemon was complaining to the log about 
> problems with opening some files. Either the mysql socket or the detail log 
> file. The server is pretty loaded (up to1.600 req/s in peaks). I have about 
> 600 connection to the DB.

  Again, that's likely a problem with the DB.

> It looks that problem appeares when the rate goes 
> over 1.100 req/s. Of course the bottleneck is the DB. On the other hand there 
> is not too much to do on the DB side. Having ~1 million of sessions in a 
> InnoDB table with the rates mentioned above is not easy. Nevertheless I am 
> trying to tune the best config for this purpose...

  Don't tune FreeRADIUS.  Tune the DB.  It's the source of the problems.

  Why are there 1M rows in the InnoDB table?  If they're historical, move them to a separate table.  Have one "live" session table, and another"historical" table for closed sessions.  Fix your schema so that it has the correct indices.

  No amount of poking FreeRADIUS will make the database run faster.  Any changes to FreeRADIUS just work around the issue.  They don't fix the issue.

  Alan DeKok.