I'm getting a little concerned as I run a small server hosting a number of websites and manage the email for a few dozen people.
Just recently though I've had a couple of notifications from spamcop alerting me that spam has been sent from my server, and when I have a look over the logs from time to time I can indeed see that there are many repeated attempts of mail being sent from my server. Most of the time it gets knocked back from the destination servers but sometimes its getting through.
Unfortunately I'm not linux or postfix expert, I can get by but had though I had my machine locked down quite securely, I don't allow relaying, when I check the online DNS/MX tools they tend to report my server as being OK so I'm not sure where to take it now and hoping someone might be able to throw me a few pointers.
I get lots of entries like this in my MAIL.INFO log
Jan 2 08:39:34 Debian-50-lenny-64-LAMP postfix/qmgr: 66B88257C12F: from=<>, size=3116, nrcpt=1 (queue active) Jan 2 08:39:34 Debian-50-lenny-64-LAMP postfix/qmgr: 614C2257C1BC: from=<email@example.com>, size=2490, nrcpt=3 (queue active)
Jan 7 16:09:37 Debian-50-lenny-64-LAMP postfix/error: 0A316257C204: to=<firstname.lastname@example.org>, relay=none, delay=384387, delays=384384/3/0/0.01, dsn=4.0.0, status=deferred (delivery temporarily suspended: host mx.fakemx.net[126.96.36.199] refused to talk to me: 421 mx.fakemx.net Service Unavailable) Jan 7 16:09:37 Debian-50-lenny-64-LAMP postfix/error: 5848C257C20D: to=<email@example.com>, relay=none, delay=384373, delays=384370/3/0/0.01, dsn=4.0.0, status=deferred (delivery temporarily suspended: host mx.fakemx.net[188.8.131.52] refused to talk to me: 421 mx.fakemx.net Service Unavailable)
then there tends to be connection timeouts, so from what I see even though I had relaying disabled.. something is getting by and trying to send..
So if you can help that will be greatly appreciated, and any further logging/config info I can supply.
A few lines from the Main.CF which I thought were sufficient are as follows, maybe I'm missing something important here :
# Requirements for the HELO statement smtpd_helo_restrictions = permit_mynetworks, warn_if_reject reject_non_fqdn_hostname, reject_invalid_hostname, permit # Requirements for the sender details smtpd_sender_restrictions = permit_mynetworks, warn_if_reject reject_non_fqdn_sender, reject_unknown_sender_domain, reject_unauth_pipelining, permit # Requirements for the connecting server smtpd_client_restrictions = reject_rbl_client sbl.spamhaus.org, reject_rbl_client blackholes.easynet.nl, reject_rbl_client dnsbl.njabl.org # Requirement for the recipient address #smtpd_recipient_restrictions = reject_unauth_pipelining, permit_mynetworks, reject_non_fqdn_recipient, reject_unknown_recipient_domain, reject_unauth_destination, permit smtpd_recipient_restrictions = reject_unauth_pipelining,reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination,check_policy_service inet:127.0.0.1:60000,permit # require proper helo at connections smtpd_helo_required = yes # waste spammers time before rejecting them smtpd_delay_reject = yes disable_vrfy_command = yes