So my VPS provider has blocked port 25 on my server’s IP, apparently due to spam. I’ve had a bit of a look at mail.log & auth.log but I can’t see any unauthorized use of the server and I know authenticated users haven’t been spamming. Also, the VPS provider’s logs indicate very low outbound bandwidth usage.
The VPS provider has suggested I use port 587 for mail service.
Is is possible my server is being used an a spam relay? If so, how can I prevent it? Or, is my VPS provider full of it?
Running 0.09 (can’t update to 0.10 without port 25 open…)