RainDrop Laboratories Status

As some have been noticing, the increasing spam load has been driving the mail server into defensively rejecting new connections while it processed the crap being fed to it.  This makes it difficult for mail client programs to send mail, which don’t queue it up the way other servers do.

For a short term fix, I’ve adjusted the timeouts on sendmail in order to try to cut down the impact of the incoming spam.

The long term solution is to setup a separate server for outgoing mail that won’t be affected by the incoming mail.  While the server itself isn’t hard to setup, enabling it to authenticate (i.e. you login to send mail, required to prevent it from becoming a spam relay itself) is a much thornier problem…

The new machine is pretty much operational, and I’ve been digging into the mail server interface on the spam filter, but it’s not being cooperative.  I may have to replace it, but I’ll give it another go here shortly…

I sold my desktop machine wednesday night (while it was still worth something useful ;-) ) and bought it’s replacement yesterday; with backing up the old one and getting the new one setup, that’s set things back a few days, but I should get back to the spam filter this weekend…

The code to handle individual recipients accordingly is there, but the smtp library that interfaces it to the mail system is throwing some roadblocks in the way it handles temp files.  I think that’s mostly fixed, but there’s still some debugging to do.  Probably won’t be able to get to it until tomorrow night though…

Progress is being made on the new spam filter; the sticking point at the moment is dealing with the case where some recipients of a message want filtering and others don’t.  Hopefully I’ll get through this one tonight, and then it’ll just be a matter of building a user interface to the settings and quarantine area…

Spam has increased dramatically lately, and the old filtering on agora is even less capable of coping. There is help on the way though: I’m making good progress on a new front end filter that will not only be running current spam and virus filtering, but it will eventually allow better user control over how it works. It currently does:

• white/blacklist processing
• greylisting (if mail hasn’t been seen before from this sender, issue a temporary error once and see if they retry it — real servers will, spammers often won’t — this is cutting the load in half on agora even now)
• spf (checks to see if the mail is coming from a server authorized to send mail from the sender’s stated domain, for those domains that have listed authorized servers, this cuts down on forged mail)
• checking with a current version of spamassassin to see if it’s spam or not

Still to do:

• quarantine suspected spam
• check with a virus checker (clamav) and quarantine suspected virii
• provide user access to white/blacklists, quarantine and enable/disable various filter options

I should have the spam and virus checking working this week, and hope to have the user interface done next week.

If anyone gets a reasonable amount of mail (at least several daily) and wants to be a guinea pig, let me know (preferably if you have your own domain, but there’s some value in forwarding through it as well…)!