dhcp and cache question

[Alan DeKok]

On Jul 21, 2016, at 9:29 AM, Anton <zav at tomica.ru> wrote:
> Here is the static database(pool) mac2ip and dynamyc sql database(pool) sqlippool. ma2ip is checked first
> if we have match in mac2ip then we use it, else we use dynamic ip-address from sqlpool. It works.

  That's good.

> mac2ip works fast but sqlippool uses mysql and get some CPU load -- there are some crazy
> devices in the network which ask dhcp all the time and fast (misconfigured or brocken routers?).
> Mysql eats the CPU :-).

  This is a common problem.

> How can I use rlm_cache module in this configuration to speed up and reduce CPU load ?

  Cache DHCP replies.  Then when a request comes in, check the cache.  If the request is received within a short time of the previous request, just return the same cached data, and avoid MySQL.

> I cannot understand how to use rlm_cache. Please explain me with examples on my configuration.

  Well, we're not going to do all of your work for you.  Perhaps you can ask specific questions about the cache module.

  The cache module is documented in raddb/mods-available/cache.

  What part is unclear?  What did you try to configure?

  Alan DeKok.