Ignoring too-frequent accounting packets from buggy NAS

[Arran Cudbard-Bell]

On 26 Oct 2012, at 13:53, Phil Mayers <p.mayers at IMPERIAL.AC.UK> wrote:

> All,
> 
> We are having a problem with our Cisco lightweight wireless since a recent firmware upgrade. I am delving into it, and will probably open a TAC case, but in the meantime I need a solution.
> 
> The specific issue is that the NAS is sending interim accounting very, very frequently, in violation of the spec, its own config, and the Acct-Interim-Interval.
> 
> My suspicion is that the device is sending an accounting update whenever some internal "update" occurs (e.g. migrate to a new AP) and that this is an unintended side effect of some internal changes.
> 
> This is killing our SQL database :o(
> 
> Until I can get this fixed, can anyone think of an easy way to throw away interim accounting requests for a given "key" and time window? I'm wondering if rlm_cache can be made to do it?

It can, see wiki :)

http://wiki.freeradius.org/modules/Rlm_cache

In fact it documents your *exact* use case with config examples and everything. *twilight zone music*

-Arran