We're running ISA Enterprise on 2000 Server, dual 2.4 Xeons, 4GB RAM, with N2H2's BESS filtering plugin. It works great.
We have another server running SQL Enterprise 2000 on 2000 Server, single 2.4 Xeon, 4GB RAM. Nothing is using it at the moment.
Both systems are on the same internal switch, running at 100FDX.
I've enabled ISA to log to the SQL server. Everything seems to work great -- except for one problem:
Our typical load is around 600 (anon SecureNAT) clients. This pulls around 50% CPU utilization with +/- 20% spikes, and gets pretty close to full utilization of our 11MB upstream link.
When I enable SQL logging, CPU utilization drops to a near-constant 30%, and upstream traffic bandwidth drops down to about 6MB. Needless to say, performance hits the floor. Some sites will even begin to time-out.
I've tried a dedicated NIC on both the SQL and ISA boxes with a crossover cable between, with the same results.
SQL seems to be performing fine, pulling 150-200tps with under 7% CPU utilization and occasional disk access.
Any suggestions for eliminating this performance issue?
I've tried limiting the fields used by ISA logging, but that only seems to work for the file-based logging -- SQL wants the whole enchilada.
I've also tried only logging the web proxy log. That helps, but still has a noticeable impact.