I talked about the joys of running my own mail server last week only to find that my mail server was broken yesterday. Spamassassin stopped doing DNS lookups for RBL and SPF checks. I had one of these moments:
My logs looked like this: plugin: eval failed: available_nameservers: No DNS servers available! plugin: eval failed: available_nameservers: No DNS servers available! rules: failed to run NO_DNS_FOR_FROM RBL test, skipping: (available_nameservers: [.