I got a centos machine that I am configuring send mail for. It has been working for the past couple of weeks. But around last week suddenly the sendmail stopped sending emails. var/log/maillog doesn't show any obvious errors. I tried the suggestions in the following post about changing the daemon option to not include the localhost as per post here:

Where to check log of sendmail?

but here is the thing: I got another identical server with the localhost included in the daemon option and that one is working fine.

I found that if I reboot the sendmail service it can start the queued mail messages.

Has anyone seen this before?


  • Can you please elaborate on the symptoms? When the issue occurs, does it stop sending all emails? Or just stop processing deferred/queued messages? Is the daemon listening on port 25 during this issue? What happens if you manually try connecting to the host via a telnet test? – Mike B Mar 16 '15 at 16:10
  • The symptom is just that the mail doesn't get sent, all messages does not get sent. It seems to hold it in queue/deferred and that's it. The daemon is listening on port 25. – D.Zou Mar 16 '15 at 19:37
  • 1
    What happens when you telnet to the system while the issue is occurring and try sending a message? How far in the SMTP transaction does it get? – Mike B Mar 16 '15 at 23:44

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Browse other questions tagged or ask your own question.