OT: Blocking persistent spammers using IPTables?

[Jason Ede]

We're debating blocking (using IPTables) IP's that register more than a set number of rejections (554 from spamhaus and other blacklists or persistently try random address at domain). Before we actually implement this I'm wondering if there can be any problems with this method? It will only be used for IP's that try to connect a significant number of times and we'll have an expiry on each IP so the blocklist doesn't keep growing indefinitely.

Jason
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.mailscanner.info/pipermail/mailscanner/attachments/20100427/4415e7b2/attachment.html