Debian 8 x64 problem with timeout mailserver

Discussion in 'Installation/Configuration' started by Niubbo75, Oct 25, 2016.

  1. Niubbo75

    Niubbo75 Member

    Hello to all, I have a problem with a Debian 8 server installed following "The Perfect Server - Debian 8 Jessie (Apache2, BIND, Dovecot, ISPConfig 3)"
    I have a customer that have 120+ email accounts and all of them are connected from the same IP address, they use Thunderbird for email client (but I have try also with Outlook 2016 and Mail on Apple) and the can't read/write email because thunderbird still go in timeout.
    I have try to change mail_max_userip_connections in /etc/dovecot/conf.d/20-imap.conf (actually I have set it to 35000) but w/out any success (I have ofcourse restart dovecot service and also try to restart the server but nothing change). Really I don't know what to do to fix that problem, this is my first experience with Debian, in past I have always use CentOS and I have never had this kind of problem :(
    Any help will be very appreciate as usual.
    Thanks in advance, Alessandro.
     
  2. webguyz

    webguyz Member HowtoForge Supporter

    Sounds like a connection issue. Are you using fali2ban? If so stop it. Can you do a simple connect test with telnet?
    Telnet my.mailserver 25
    Verify your getting a response back.
     
  3. Niubbo75

    Niubbo75 Member

    Hello webguyz and thanks for your reply.
    I've try to connect via telnet (both with fail2ban running & stopped) and I connect w/out problem, if can help, I can also login w/out problem to mailboxes using Roundcube and also with Thunderbird, Outlook (any version) Mail and so on if I use an IP different from the one used by the customer (and he have a static IP so it never change), customer can use mailclients w/out problem till there are at least 5 people/mailclients, if someone else turn on his mailclient (and sure they do) than I got this issue.
    Any other customers on that mailserver can use their mailclients w/out issues also if they have same mailboxes on desktop, smartphones and tablet.
    Issue is only with that customer that have a lot of mailboxes from the same place and IP.
     
  4. Niubbo75

    Niubbo75 Member

    Up, anyone have some ideas?
     
  5. webguyz

    webguyz Member HowtoForge Supporter

  6. Turbanator

    Turbanator Member HowtoForge Supporter

    Are you showing any errors/issues in your /var/log/mail.err or mail.warn files? Also are you saying on TB is having this issue, or any email client from that IP?
     
  7. webguyz

    webguyz Member HowtoForge Supporter

    Try posting on a Postfix forum? If a problem has seen before it would the best place to try and find the problem.
     
  8. Niubbo75

    Niubbo75 Member

    Thanks webguyz but no, is not an smtp problem, I have problem with IMAP, I can see it from Mail (MACOS debug logs) I haven't any SMTP timeout but I have it on IMAP.
     
  9. Niubbo75

    Niubbo75 Member

    If I try from any email clients I have the issue, but if I use webmail, I have no issues also if I connect all the mailboxes from the same IP but via webmail, on CentOS same hardware I have never had this kind of issues, maybe I'll setup a new server and migrate from Debian 8 to CentOS 7, I have try Debian but maybe is not for me.
     
  10. Niubbo75

    Niubbo75 Member

    Is not a Postfix issue, but a dovecote ones, I have no problem to delivery mail messages, but I have problems to let user connect via mailclients from the same IP address, if I connect the same mailboxes via emailclients (any kind of that) but via different IP addresses I have no issues, issues are only from the same IP address, that's why I have think about mail_max_userip_connections and I have change that value to a big one but with no success.
     
  11. Niubbo75

    Niubbo75 Member

    /var/log/mail.err contains only 2 lines with unexpected command-line argument: reject, but they are of today, one at 10:35 am and one at 4:45 pm, /var/log/mail.warn contains only info about failed login from unknow (someone who try to access mailserver w/out fortune, eh eh) and I have check all IP and no one is the one of my customer (all IP are out of Italy, all my customers are in Italy like me).
     

Share This Page