Freeradius performance problem

[Alan DeKok]

Giuseppe Marocchio wrote:
> i have inherited the administration of a radius server, that
> authenticate  900 PPPoE user on mikrotik box.
> 
> i've noticed that there is some performance problem, mikrotik box show
> that  "last request RTT" in some cases is up to 1000ms, there is some
> "resend" request and  also some "timeouts", In order to mitigate the
> problem i've  disabled  the   interim update, and the timeouts are
> drastically reduced.
> But exists.

  A 386 should handle 900 users without a problem.

> i' use mysql back-end, i've checked if there are slow queries but file
> is empty. ( of course is enabled... )

  <shrug>  Performance issues are almost always the DB.

> the server is a dual core Xeon 3.0Ghz with 1 Gb of ram. 
> The SO is debian Linux stable,  freeradius is   2.1.10 installed by
> debian package.

  So it's not the RADIUS server which is the problem.  That amount of
CPU power is more than enough.

> Any ideas?

  Fix the database.

  If you don't think it's the DB, configure a test server on the same
machine which doesn't use the DB.  It will handle 2000+ packets per second.

  Alan DeKok.