Problem with Fedora1 and ipop3d

[Rick Stevens]

Tim Alberts wrote:
> On Thursday 22 April 2004 12:54, Alexander Dalloz wrote:
> 
>>Am Do, den 22.04.2004 schrieb Tim Alberts um 21:48:
>>
>>>I changed no permissions from the default.  The permissions are as
>>>follows:
>>>
>>>ls -ld /var/ /var/spool/ /var/spool/mail/ /var/spool/mail/talberts
>>>drwxr-xr-x   30 root     root         4096 Apr 15 14:19 /var/
>>>drwxr-xr-x   25 root     root         4096 Feb 12 16:11 /var/spool/
>>>drwxrwxr-x    2 root     mail         4096 Apr 22 11:47 /var/spool/mail/
>>>-rw-rw----    1 talberts mail          556 Apr 22 11:50
>>>/var/spool/mail/talberts
>>
>>So which client do you use? Please be more descriptive what exactly you
>>do. I only saw the maillog error message complaining about wrong mailbox
>>permissions on bugzilla when someone did use mutt with wrong setup.
>>
>>Alexander
> 
> 
> I got this to happen on two Fedora Core 1 systems.  My network mail server 
> which is a heterogeneous with Windows Mac and Linux workstations.  Also on my 
> personal workstation after I discovered the problem I tested it on my own 
> system.  Full install of Fedora core 1 with nothing special I can think of to 
> mention.
> 
> I need to explain further that the error message is in /var/spool/mail/user 
> file, but when I use pop3 (via kmail on localhost, or over the network) to 
> get the email I don't get the message downloaded, I don't get any errors from 
> the client side.  I also don't get any emails delivered either.  I have to 
> log into the server and access the /var/spool/mail/user file direction to see 
> the error message.
> 
> After the error occurs, I can delete /var/spool/mail/user and the thing will 
> work again for a short period of time (sometimes it fais immediately).

Uhm, hmmm.  That smells of several possible issues.  One would be
multiple simultaneous POP sessions on a single mailbox and the pop
server isn't arbitrating them correctly.  That's caused by the pop
server ignoring the lock files or flock() results.

Another would be multiple POP servers talking to the same mailbox.
/var/spool/user isn't on an NFS mount, is it?  You don't have multiple
POP servers talking to it, do you?  Without modifying code, multiple POP
servers won't work right with NFS-mounted mailboxes.  POP servers, by
default, depend on the file locking mechanisms in the kernel to
arbitrate access.  These locks are not shared by multiple servers, so
system B won't know if system A already has the mailbox open