[isp-dns] Re: Concerns about high Load

[Len Conrad <LConrad@...]

> I am currently configuring a server that will act as a mail gateway/hub 
> for a another load stricken server.
I've just installed IMGAte for an ISP whose sendmail mailbox server was 
submerged trying to do anti-abuse and take care of the users.  IMGate fixed 
his wagon immediately.

>  The setup is as follows. We have one P3 500 Mirapoint appliance 
> (www.mirapoint.com) which is acting as a mailstore and admin interface to 
> mail accounts using roughly 1100 domains. This is struggling with smtp 
> delivery, virus scanning and filtering for the whole network (5000+ 
> users). We are intending to split this traffic by placing it behind a 
> mail gateway that will handle 80% of smtp delivery.
best config, but why not 100% ?

> There were only a few options regarding methods of making sendmail aware 
> of the domains that is responsible for. In the end we came down to 2 
> methods one of which is using best_mx_is_local. The documentation suggests 
> that the function should only be used on small to medium networks. So what 
> I need from you guys is some tips on how to make the name server (bind 
> 9.2.1) more efficient
Look at IMGate.MEIway.com for your anti-abuse SMTP proxy. pre-configured, 
proven, and free.

If you really think you have problems with BIND throughput (HIGHLY 
doubtful), then run BIND 8.3.4, which 30 or 40% more efficient than BIND9.

Put BIND on the MX gateway as caching only NS.

> and perhaps some opinions and/or experience of using this method in 
> moderately high usage environment. It is running on the mail gateway which 
> is a dual p3 1.13ghz, 512mb Ram, serverworks chipset.
I suppose you've already spent the $$$, but that is horribly overpowered, 
money down the tubes.   A single CPU of 1+ GHz is fine, put the $$$ in 1 Gb 
RAM (to allow room for 100's of SMTP/D processes plus  DNS cache), and 
above all in the disks, which you didn't even mention and which is the 
limiting factor of an SMTP relay.  You don't even need SCSI, two ATA100+ 
disks of 7200 RPM and 40 Gb is sufficient.

Len