Re: Qpopper continually fails to POP mail from large mbox

Gerard wrote:
> Daniel Senie <[email protected]>
> 
>> At 02:41 PM 7/18/2006, Gerard wrote:
>>> Using FreeBSD 6.1 STABLE
>>>
>>> I am continuing to have a problem with qpopper getting mail from an mbox
>>> once the file grows to any sizable capacity
>>>
>>> This is an excerpt from the /var/log/messages file:
>>>
>>> Jul 18 08:36:47 seibercom qpopper[894]: gerard at 192.168.0.3 
>>> (192.168.0.3): -ERR POP EOF or I/O Error
>>> Jul 18 08:36:47 seibercom qpopper[894]: Stats: gerard 0 0 143 
>>> 30288106 192.168.0.3 192.168.0.3
>>> Jul 18 08:36:50 seibercom qpopper[894]: I/O error flushing output to 
>>> client gerard at 192.168.0.3 [192.168.0.3]: Operation not permitted (1)
>> This message most commonly indicates the client gave up and went 
>> away. Perhaps your customer is giving up because you're trying to 
>> push 30MB of data to them?
>>
>>
>>> The recourse I have is to manually delete the contents of the mailbox. I
>>> have the latest version of qpopper installed. I am unsure as to where I
>>> could post this problem to other than here. I would like to post a bug
>>> report, but I am not sure as to where to place it.
>> This issue has been discussed at length. Generally the issue is not 
>> qpopper's fault. You haven't mentioned what version of qpopper you're 
>> running, though, it's also possible you're running an older version.
>>
> The program version is 4.0.9, so it is not obsolete.
> 
> Here is how the problem plays out.
> 
> 1) Use fetchmail to harvest mail from main mail server - but leave the
> mail on the main server.
> 
> 2) Attempt to POP the mail off my server
>    a) If the mbox reaches a certain threshold, the downloading of mail
>       will fail.
> 
> 3) Attempt to download the mail left on the main server
>    a) Success

 From the fetchmail faq:

> S1. How can I use fetchmail with qpopper?
> 
> Qualcomm's qpopper is probably the best-of-breed among POP3 servers,
> and is very widely deployed. Nevertheless, it has some problems which
> fetchmail exposes. We recommend using IMAP instead if at all
> possible. If you must talk to qpopper, here are some problems to be
> aware of: Problems with retrieving large messages from qpopper 2.53
> 
> Tony Tang <[email protected]> reports that there is a bad intercation
> between fetchmail and qpopper 2.5.3 under Red Hat Linux versions 5.0
> to 5.2, kernels 2.0.34 to 2.0.35. When fetching very large messages
> (over 700K) from 2.5.3, fetchmail will hang with a socket error.
> 
> This is probably not a fetchmail bug, but rather a symptom of some
> problem in the networking stack that qpopper's transmission pattern
> is tickling, as fetchpop (another Linux POP client) also displays the
> hang but Netscape running under Win95 does not. The problem can also
> be banished by upgrading to qpopper 3.0b1. Bad interaction with
> fetchmail 4.4.2 to 4.4.7
> 
> Versions of fetchmail from 4.4.2 through 4.4.7 had a bad interaction
> with Eudora qpopper versions 2.3 and later. See X5 for details. The
> solution is to upgrade your fetchmail.

If the problem doesn't occur without fetchmail, why aren't you looking 
at fetchmail. Blaming qpopper for it seems a bit odd. After you fetch 
the mailbox to your server you should diff it against the original on 
the main server to see what fetchmail may be mangling...

Ken
Pacific.Net


> I have seen this problem mentioned many time. I have been advised to
> dump my present mail system and install an 'imap' system with 'dovecot'
> to handle mail delivery. Even the fetchmail manuals describe a problem
> with qpopper and a large mbox(s).
> 
> If you know of a solution, I would appreciate hearing about it.
> 
>