POP access slow across local network

[slylos]

I've got qmail/vpopmail running, with a tcpserver daemon listening on port 110 for POP access (with vchkpw as the PAM). For some reason, POP access across the local network is slow as molasses, but POP access from across the internet is almost instantaneous - any idea's?

P.S. I've got clients on the local network (and same subnet) configured as the POP and SMTP address is the internal IP address of the mail server.

 

[thedaver]

DNS name resolution is a factor in the use of tcpserver and other inetd workalikes... or is it POP3 doing DNS.

Nonetheless, you need to tell the daemon NOT to do DNS reverse lookups against the client. Don't have the resources at my fingertips to coach you on the steps.

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[slylos]

I just read somewhere that if I add the '-H' flag to my startup script for tcpserver, it will disable reverse-dns - but that article applied to the supervised tcpserver binary that listens for SMTP. I assume it will work the same with the tcpserver binary that listens on port 110 also?

 

[thedaver]

Yes, tcpserver is functionally comparable to inetd, xinetd - they all are "port listeners" that kickoff a program/daemon when suitable traffic hits a port.

You may find online a number of tcpserver scripts that handle POP3 for qmail as well.



D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[slylos]

I just added the '-H' flag to the tcpserver binary that listens on port 110, but it didn't seem to help. Any idea's?

 

[thedaver]

You DID restart the tcpserver right?

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[slylos]

Yep, restarted tcpserver. Here's my order of operation:

1. qmailctl stop
2. killall tcpserver
3. qmailctl start
4. run pop3 startup script with the '-H' flag:

env - PATH="/var/qmail/bin:/usr/local/bin" \
tcpserver -H 0 pop3 /var/qmail/bin/qmail-popup domain.com \
/home/vpopmail/bin/vchkpw /var/qmail/bin/qmail-pop3d Maildir &

Here's an interesting tid bit - POP access from a Windows 2000 Server is fine, but from a Windows XP machine on the same network is slo

http://wwww.

Also, SMTP accessing from the Windows XP machine is also fine! I don't get it!!

 

[thedaver]

Here's my /var/qmail/supervise/qmail-pop3/run file

#!/bin/sh
exec /usr/local/bin/softlimit -m 4000000 \
/usr/local/bin/tcpserver \
  -H -l mail.myhostname.com \
    -v -x /etc/tcp.pop3.cdb -c 30 -R 0 pop3 \
    /var/qmail/bin/qmail-popup mail.myhostname.com \
    /home/vpopmail/bin/vchkpw /var/qmail/bin/qmail-pop3d Maildir 2>&1

I don't recall the function of the "-l" parm is, perhaps you should look into it?

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[slylos]

What does this line do:

-v -x /etc/tcp.pop3.cdb -c 30 -R 0 pop3

I was looking around for a supervise script for pop access, but couldn't find one.

 

[thedaver]

That does some allow/disallow based upon IP of remote box. Latter bits control number of POP3 daemon sessions concurrently and which port to bind to.

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[slylos]

Any other idea's? I'm not sure what I am missing, but I really need to fix this soon, so any help is greatly appreciated!!

 

[thedaver]

I notice you are not using "-R" option...

see

http://cr.yp.to/ucspi-tcp/tcpserver.html

Helps?

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/

 

[thedaver]

PLEASE ALSO check that inetd, xinetd are NOT also running and trying to monitor the port. A longshot, but worth mentioning.

D.E.R. Management - IT Project Management Consulting

http://www.dermanagement.com/