Zimbra, TLS and MTU

I had some TLS incomming connection issues with my Zimbra (5.0) mail server.  Some but not all TLS connections where having this problem:

Apr  3 15:04:30 mail postfix/smtpd[7305]: timeout after DATA from

I haven’t found a conclusive solution, but the either restart postfix or adjusting the MTU on the mail server interface may fix the problem.

Some references:

  1. http://www.zimbra.com/forums/administrators/11840-solved-some-outside-emails-being-delayed-4.html#post61541
  2. http://www.irbs.net/internet/postfix/0511/1168.html

2 Comments

  1. ekosch Said,

    May 26, 2010 @ 3:25 am

    what mtu size you used?

    i try change the mtu size but still no luck

  2. Nicholas_Lee Said,

    May 25, 2010 @ 10:56 pm

    I forget what I used previously with vmware. I'm now using a mtu of 1500 under kvm and haven't noticed that same problem.

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