Results 1 to 2 of 2

Thread: IMAP clients work very slow

  1. #1
    jackson is offline Intermediate Member
    Join Date
    Aug 2010
    Location
    Kiev
    Posts
    16
    Rep Power
    5

    Unhappy IMAP clients work very slow

    Hello.
    Tomorrow we migrate to new Zimbra server (net hardware, new OS, new Zimbra version).
    was: Release 7.1.3_GA_3346.DEBIAN5_64 DEBIAN5_64 FOSS edition.
    now:Release 8.0.4.GA.5737.UBUNTU12.64 UBUNTU12_64 FOSS edition.
    for migration we use Zextras backup/restore

    Migration was completed successfully, but now we have big troubles with IMAP mail clients.
    I have over 150 Thunderbird email clients, which use IMAP with SSL. and all clients have a big troubles - IMAP work very slow.
    I don't have any troubles with Zimbra mailbox WEB-interface, but access to Admin panel also work extremely slow.

    at top I can see that server not overloaded (new hardware has more performance at old server we don't have such problems).
    at trafshow I saw what only couple clients generates traffic (I thins it's IMAP sync).

    I have no idea, where I should look for problem. Any help will be appreciated!

  2. #2
    jackson is offline Intermediate Member
    Join Date
    Aug 2010
    Location
    Kiev
    Posts
    16
    Rep Power
    5

    Default

    Small update (may be useful for someone):
    first time Zimbra IMAP was overloaded because all IMAP clients made full sync of mailboxes at one time. Due to Performance Tuning Guidelines IMAP can have a problem with too many concurent connections.
    In couple of days problem gone.
    But from last Friday it came again.
    After log check (/opt/zimbra/log/mailbox.log) I find a source of problem:
    I have couple of Outlook users, which use IMAP. Every time, then Outlook connect to IMAP, it oper thosen of concurent connections - for each IMAP folder and overloads IMAP service.
    Now I'm looking for Outlook configuration for IMAP to prevent that DDoS to mail server...

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Outlook Imap Slow other Clients Fast
    By pinkstond in forum Administrators
    Replies: 3
    Last Post: 12-28-2012, 09:13 PM
  2. HTML Email doesnt work for Mobile clients
    By alexdog69 in forum Mobility
    Replies: 1
    Last Post: 04-08-2010, 10:27 AM
  3. Spamassassin for IMAP clients (outlook)
    By sorcererbob in forum Administrators
    Replies: 3
    Last Post: 09-05-2008, 09:44 PM
  4. COS Settings for IMAP Clients
    By soxfan in forum Administrators
    Replies: 0
    Last Post: 11-17-2006, 10:20 AM
  5. Linux Firefox Clients Don't Work with Spell Check
    By SiennaWarrior in forum Users
    Replies: 12
    Last Post: 04-03-2006, 10:07 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •