I’m sure some of you have noticed that I’m experiencing occassional server problems. The host I’m on has been overtaxed, mostly due to spammer activity (both web and email varieties). There are times when the server load spikes up into the 20s, which is ridiculously high. To combat the problem, I set up a cron job which monitors the load level, and restarts apache and mysql when it goes above a certain threshold. However, for some reason, the mysql database server sometimes fails to restart properly. I’ve just added another monitor program which should fix that, so the database should never stay down for more than a couple of minutes. I still need to put something in place to do something more proactive about the email spam, though. Part of the problem there is that the volume of spam email is causing SpamAssassin and procmail to hog the CPU. I may need to enable some of the more aggressive SpamAssassin features.
I’ve been told that we’ll be getting some new hardware soon, so hopefully things will settle down more when that happens. It should also give me an opportunity to do some better performing tuning for the server.
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What SA features would you be considering using, Dougal? Sometimes I have the same problem [although I run off a dual-CPU box, so this isn't so much a problem anymore ...].
To be honest, I’m not sure. I’m not the person who set SA up on the box originally, so I’m still trying to get a handle on how it’s configured right now. Basically, though, I think all it’s doing now is tagging messages. I’m thinking that I should consider rejecting messages from RBL blacklisted sites outright, at the SMTP level.
SA was killing my server so often that I stopped using it. Performance has not been a problem since.
Right now, most of the problem stems from trackback spammers. The trackbacks don’t get through, due to a good blacklist. But the horsepower required to process trackbacks coming in so fast is what’s killing the server most of the time.
I’ve modified my system monitoring scripts so that when the load threshold is triggered, it temporarily renames the trackback module, then re-enables it after a five minute sleep.
all sent mail is being daemon server and not sent
what should I do
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[...] Spam Assassin One of the WordPress gurus posted a blog entry about server problems he’s been having, relating to huge SPAM load. Looks like the same [...]
Server problems
[...] of the WordPress gurus posted a blog entry about server problems he’s been having, relating to huge SPAM load. Looks like the same problems I was having that [...]