Re: [vchkpw] Intermittent pop3 authentication failure

[Jason Mann]

On 20031119 1052, Michael Bowe wrote:
 file locking is used in several places throughout vpopmail
 
 However the only place I have ever heard of it causing problems is inside
 the roaming user functions.
 
 Usually you would need to have a fair number of POP3 logins happening before
 you run into locking problems. Perhaps consult your POP3 logs and look to
 see if you are recording a high number of POP3 connections.
 
 The problem is exacerbated when you are using CDB auth backend rather than
 MySQL backend. MySQL removes some (but not all) of the file-based operations
 for the roaming users code.
 
 Michael.

Hi Michael.

Thanks for your reply.

I have consulted the logs, and it seems that there are never more than 9
concurrent pop3 connections, as reported by tcpserver.

The server is currently handling a small numbers of mailboxes - only a
tiny fraction of the intended total. If it's struggling to keep up already, I
dread to think how it will handle the rest.

The box itself isn't exactly slow. It's a 1.7GHz Celeron, with a gigabyte of
RAM, and twin 80Gb ATA100 disks in hardware ATA-RAID mirror config. The disks
are both masters on seperate channels.

I know this isn't ideal server spec, but the client has a very limited budget
at the moment. Even so, I would expect it to be able to cope fairly easily.

Can you, or anyone else, make any recommendations on trying to avoid or
improve this bottleneck? I have been considering moving the entire
~vpopmail/etc directory onto a memory based filesystem for quicker access,
with a backup copy on hard disk. What do you think of that idea?

Moving to MySQL isn't ideal, due to my lack of experience with it.

Many thanks in advance.

Jason Mann

Re: [vchkpw] Intermittent pop3 authentication failure

[Michael Bowe]

file locking is used in several places throughout vpopmail

However the only place I have ever heard of it causing problems is inside
the roaming user functions.

Usually you would need to have a fair number of POP3 logins happening before
you run into locking problems. Perhaps consult your POP3 logs and look to
see if you are recording a high number of POP3 connections.

The problem is exacerbated when you are using CDB auth backend rather than
MySQL backend. MySQL removes some (but not all) of the file-based operations
for the roaming users code.

Michael.


- Original Message - 
From: Jason Mann [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Sent: Tuesday, November 18, 2003 10:07 PM
Subject: [vchkpw] Intermittent pop3 authentication failure


 Hi folks,

 I have recently built a qmail/vpopmail server for a client of mine, to
handle
 mail for the hundreds of domains that they host for their customers. That
 said, the server is currently under a very light load as only a few
domains
 have been set up on it, and each domain only has a small number of
mailboxes.

 The server is based on the following software:

 FreeBSD 4.8-RELEASE-p13
 qmail-1.03 (from FreeBSD ports)
 vpopmail-5.3.28 (from FreeBSD ports)

 I have the pop3 service running as follows:

 /usr/local/bin/tcpserver -H -R -v -c 200 0 110 /var/qmail/bin/qmail-popup
\
 mail.domain.co.uk /usr/local/vpopmail/bin/vchkpw \
 /var/qmail/bin/qmail-pop3d Maildir

 Since the server was set up, my client has been seeing intermittent pop3
 authentication failures, where valid username/password pairs are not
 accepted. This state usually persists for a few minutes and then clears,
 allowing authentication.

 Today, however, my client got a different error. When I tried to login via
 pop3 using a test account, I got this error message (in Outlook Express):

 -
 There was a problem logging onto your mail server. Your Password was
 rejected. Account: 'XX mail server', Server: 'xx.xx.xx.xx', Protocol:
 POP3, Server Response: 'File busy try again later!', Port: 110,
Secure(SSL):
 No, Server Error: 0x800CCC90, Error Number: 0x800CCC92
 -


 I had originally wondered if the auth failures were related to the vchkpw
 process - perhaps the open-smtp file was too busy. This latest error seems
to
 reinforce my suspisions.

 Can anyone make any suggestions here, either with what the problem might
be,
 or what to do to find out what the problem is?

 I can provide additional information on the set up if it is required.

 Many thanks in advance.

 Jason Mann