On Tue, Aug 28, 2007 at 06:08:30AM -0700, Marc Perkel wrote: > Mark de Vries wrote: > > On Mon, 27 Aug 2007, [EMAIL PROTECTED] wrote: > >> we have several servers which handle incoming smtp-connections as a > >> loadbalancing-setup, which also make use of the ratelimit-database. > >> > >> one main disadvantage is, that you had to multiply the rate by the > >> number of hosts in the setup. > >> > >> is it possible to share the ratelimit-hints-database across several > >> hosts - e.g. by NFS? are there some pitfalls, especially when the > >> nodes are on high load/traffic? > > > > I have wondered about this myself. Althoug I would be more interrested in > > sharing the callout cache between several servers.... > > > > If anyone tried and would like to share there findings that would be > > great. > > I'd love to have it too - but I had assumed that it wasn't possible. In > my case in particular because I have hosts in multiple locations and if > the central host fails the other hosts would need to switch to > independent rate limiting. But I'd love it if it magicall worked.
If you are using a hardware or software load balancer, check to see if your balancer has the ability to do IP-persistent load balancing. That would allow you to ensure that all IP addresses (perhaps within a specific time frame) would always go to the same server. It's not ideal, but if you tend to only care about short-term ratelimits (such as how many messages per hour, etc), then this works wonderfully and is how we eventually dealt with the issue. SQL storage for rate-limits isn't ideal without some sort of intervening proxy daemon given the (re)connection load on the SQL server on high traffic mail servers. -- Dean Brooks [EMAIL PROTECTED] -- ## List details at http://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
