Sure it will in your situation...but when you have more than one client going after the mailbox, they'll step on each other's work n vanilla Dovecot. And in this case there are at least 2 and as many as 4 or 5 mail clients all open at the same time going after an mbox format inbox. We originally had some Unpleasantness with the unsupported BB users where they left their BBs on at home and came to work and found that they would delete stuff and that it would then come back (their Macs were set to make deleted stuff disappear from the list but not be expunged until they did that....and when the BB popped up from its 5 minute nap and checked the mailbox, it would break the lock and invalidate the work). Those user now do an atomic delete with immediate expunge. And their use was simple compared to the CFO's...would you believe one of his 3 secretaries uses the Trash folder as a secondary storage area? <shudder> And cannot be talked out of it?

A large part of the time she has Pegasus running on her desktop too and we've not seen any of these problems.

I don't know of any IMAP apps to get for a BB but if you come across a good one, please post a note here.

--

Knute Johnson Molon Labe...

so far: LogicMail...V0.4.0 (not even V1.x, but O.x...is this beta?) http://www.logicprobe.org/proj/logicmail http://www.berryreview.com/2007/10/30/faq-alternative-3rd-party-email-applic... http://www.berryreview.com/2007/08/22/logicmail-free-imap-pop3-client-for-bl...

in beta, Tiggit http://www.berryreview.com/2008/02/15/tiggit-beta-another-3rd-part-email-cli... Knute Johnson wrote:

...

I don't know of any IMAP apps to get for a BB but if you come across a good one, please post a note here.

LogicMail looks interesting but it won't do StartTLS which I need.

My setup uses mbox and I haven't seen any problems with multiple clients. What is the problem that I should be having?

Thanks,

--

Knute Johnson Molon Labe...

It's been a while so I don't have the logs any more except for what was in my Sent folder........ As an example of what I am talking about, here is BB polling every 15 minutes in the maillog:

Mar 5 03:06:09 mercury mail:info imapd[2085096]: Login user=sshore host=bda037. bis.na.blackberry.com [216.9.249.37] Mar 5 03:06:09 mercury mail:info imapd[2085096]: Logout user=sshore host=bda037 .bis.na.blackberry.com [216.9.249.37]

Mar 5 03:20:39 mercury mail:info imapd[2961602]: Login user=sshore host=ten003. bis.na.blackberry.com [216.9.249.252] Mar 5 03:20:48 mercury mail:info imapd[2961602]: Logout user=sshore host=ten003 .bis.na.blackberry.com [216.9.249.252]

and here are some clients fighting over the lock

Mar 6 09:05:48 mercury mail:info imapd[970952]: Killed (lost mailbox lock) user =xxxxx host=cpe-24-161-103-11.hvc.res.rr.com [24.161.103.11] Mar 6 09:08:04 mercury mail:info imapd[844000]: Killed (lost mailbox lock) user =xxxxx host=[10.40.70.71] Mar 6 09:08:18 mercury mail:info imapd[2547784]: Killed (lost mailbox lock) use r=xxxxx host=cpe-24-161-103-11.hvc.res.rr.com [24.161.103.11]

All I know is that I had some moderately important people screaming at me (I even heard the word useless) that the mail service was %^$#ed up. That after I made it dianetically clear (took 2 weeks) to them that there Must Only Ever Be One Mail Client Open At A Time, they no longer had problems.

Scott Silva wrote:

on 3-13-2008 11:14 AM Knute Johnson spake the following:

...

...

so far: LogicMail...V0.4.0 (not even V1.x, but O.x...is this beta?) http://www.logicprobe.org/proj/logicmail http://www.berryreview.com/2007/10/30/faq-alternative-3rd-party-email-applic...

http://www.berryreview.com/2007/08/22/logicmail-free-imap-pop3-client-for-bl...

in beta, Tiggit http://www.berryreview.com/2008/02/15/tiggit-beta-another-3rd-part-email-cli...

Knute Johnson wrote:

...

I don't know of any IMAP apps to get for a BB but if you come across a good one, please post a note here.

LogicMail looks interesting but it won't do StartTLS which I need.

My setup uses mbox and I haven't seen any problems with multiple clients. What is the problem that I should be having?

Thanks,

So am I. The only time I had a problem is if multiple programs are trying to access the mbox file directly at the same time. As long as the multiple clients all go through dovecot, I don't have any problems. In fact, I often leave an instance of thunderbird running over my mailstore at my main office, and will hit the same store from my lappy, or from my other office.

I have also had thunderbird and outlook running on the same machine looking at the mailstore while I try and reproduce an error that one of my users is having, and although it can sometimes slow down a bit, I don't see any problems.

--

Stewart Dean, Unix System Admin, Henderson Computer Resources Center of Bard College, Annandale-on-Hudson, New York 12504 sdean@bard.edu voice: 845-758-7475, fax: 845-758-7035

I didn't field DC until 1.0 and have kept pretty much up to date...these problems were present with UWIMAP but got somewhat better since the switchover to DC. I can't imagine how DC could deal with two clients working on the same mbox inbox, where the first instance has changes that are local to the PC and not yet put on the server without DC breaking the lock of the first instance (and thus invalidating the incomplete changes on the PC) and giving it to the second...or is there some magic?

Scott Silva wrote:

on 3-13-2008 12:02 PM Stewart Dean spake the following:

...

It's been a while so I don't have the logs any more except for what was in my Sent folder........ As an example of what I am talking about, here is BB polling every 15 minutes in the maillog: Is your dovecot version fairly current? This looks like some of the problems I saw in the betas.

--

Stewart Dean, Unix System Admin, Henderson Computer Resources Center of Bard College, Annandale-on-Hudson, New York 12504 sdean@bard.edu voice: 845-758-7475, fax: 845-758-7035

Scott Silva wrote:

on 3-13-2008 12:58 PM Stewart Dean spake the following:

...

I didn't field DC until 1.0 and have kept pretty much up to date...these problems were present with UWIMAP but got somewhat better since the switchover to DC. I can't imagine how DC could deal with two clients working on the same mbox inbox, where the first instance has changes that are local to the PC and not yet put on the server without DC breaking the lock of the first instance (and thus invalidating the incomplete changes on the PC) and giving it to the second...or is there some magic?

I just tried to do a mass move on a mailbox with thunderbird, and tried to access the same box with outlook and it just took a little while to show up, then refreshed the headers and showed the deleted messages marked as deleted.

try the same while receiving mail... also trying moving messages one at a time, not a "mass move".

And nothing unusual in the logs. Strange.

(The mbox) size may matter... Usage too.

I've already seen mbox files being corrupted.

Stewart Dean wrote:

and here are some clients fighting over the lock

...

Mar 6 09:05:48 mercury mail:info imapd[970952]: Killed (lost mailbox lock) user =xxxxx host=cpe-24-161-103-11.hvc.res.rr.com [24.161.103.11] Mar 6 09:08:04 mercury mail:info imapd[844000]: Killed (lost mailbox lock) user =xxxxx host=[10.40.70.71] Mar 6 09:08:18 mercury mail:info imapd[2547784]: Killed (lost mailbox lock) use r=xxxxx host=cpe-24-161-103-11.hvc.res.rr.com [24.161.103.11]

All I know is that I had some moderately important people screaming at me (I even heard the word useless) that the mail service was %^$#ed up. That after I made it dianetically clear (took 2 weeks) to them that there Must Only Ever Be One Mail Client Open At A Time, they no longer had problems.

We have some users that caused this too on uw-imap with mbox, they would get frustrated that deleted mail would come back as well. I'm happy to say that Maildir with dovecot handles this extremely well, even on NFS with multiple servers in dovecot 1.1 since one of the later betas.

You might consider how to direct your needy users to a mail server instance that has Maildir. If you are afraid, or its difficult to wedge this into your current setup, you could have a completely different mail server host their mail, and you could use a MX server and/or a perdition IMAP proxy to redirect them invisibly to this other server once you've moved or copied their data. I wanted to avoid this path and get the migration over with, but I caved in and started going after the power users and the low hanging fruit. I'm very glad I did, because now I can migrate users one at a time and deal with any problems that arise on my schedule, and when I am prepared in the future, I can throw some switches and move the remaining users over that are unrealistic to handhold.

On Thu, 2008-03-13 at 15:02 -0400, Stewart Dean wrote:

...

Mar 5 03:06:09 mercury mail:info imapd[2085096]: Login user=sshore host=bda037. bis.na.blackberry.com [216.9.249.37] .. Mar 6 09:05:48 mercury mail:info imapd[970952]: Killed (lost mailbox lock) user =xxxxx host=cpe-24-161-103-11.hvc.res.rr.com [24.161.103.11]

Those are UW-IMAP messages! Dovecot doesn't kill connections over a mbox lock.

On Thu, 13 Mar 2008, Stewart Dean wrote:

Sure it will in your situation...but when you have more than one client going after the mailbox, they'll step on each other's work n vanilla Dovecot. And in this case there are at least 2 and as many as 4 or 5 mail clients all open at the same time going after an mbox format inbox.

"Doctor, it hurts when I do $foo."

"Then stop doing it!"

Is there a reason you're hurting yourself by using mbox?

-- Asheesh.

-- Deadwood, n.: Anyone in your company who is more senior than you are.

No. Other than: a) the griping fear of me personally (1 person) migrating 4000 users and b) the recurrent experience of trying to marshal everything necessary to do it, getting about a tenth of the way into *beginning* it and having some 4-alarm fire interrupt things...and then it's a month or two before things calm down again that I might take a shot at it again. These days, I've gotten cynical. I enjoy the peace and quiet for 4 hours to 3 days on the outside whereupon something else falls in the cart that I have deal with. Plus I have to wonder what the realities of moving from 1) mbox with one monster file to 2) maildir with inodes beyond measure and its effect on backup. Yes I know I should be able to just convert one user and find out...but the time isn't there for even that... Fear and Loathing, Sickness unto Death....... Remember: when you (the sysadmin) do things really, really right, nobody knows you've done anything. Sounds like a 0 to negative sum game......

Benjamin R. Haskell wrote:

Any particular reason you're tied to mbox other than having migrated from UW-IMAP? I suspect maildir, though not as lock-free as advertised, would have a much better time of things. (i.e. it's far better suited for multiple-client access.)

--

Stewart Dean, Unix System Admin, Henderson Computer Resources Center of Bard College, Annandale-on-Hudson, New York 12504 sdean@bard.edu voice: 845-758-7475, fax: 845-758-7035