sato x wrote:
Dear guys,
I have a qmail-ldap server that running well, except for its speed.
When a client sends a message (a simple one with text only), it will
take about 8 seconds for the email to disappear from the Outbox (I
mean, the time needed for email to get sent).
I tried to raise the number of users into 23, and sent email in the
same time (a couple times). The average time needed to send those
emails raised to 16, 25, 50 seconds. It even took over 1 minute for
some users. The receivers were local and remote (e.g., gmail.com).
Currently we're running a qmail server (qmailrocks installation), and
the time we need to send and email is only about 1 - 2 seconds (the
time it needs to process emails was even faster than the qmail-ldap
server). Was the location of the LDAP server has caused this? Below
is the architecture of our network. Both the qmail server and
qmail-ldap server were in the same network (DMZ), the LDAP server was
in the local network (LAN). *SW = core switch
LAN -------------|-----|SW|--------- FIREWALL/ROUTER
--------------------- INTERNET
LDAP server ---| |
Squid proxy ---| |
File server -----| |
DMZ-switch
_____________|__________
| |
| |
qmail-ldap server qmail-server
Is there a way to tune qmail-ldap server so it can work (at least) as
fast as the existing qmail server? I really need help due to this
problem and I will appreciate every single clue. Thank you in advance.
Regards,
sato
PS. I have a couple server that utilize the LDAP server :
1. Samba PDC for windows domain, about 300 users
2. Samba Winbind for squid proxy authentication, 150 users
3. Samba file server that heavily used, 300 users
Hi Sato,
when you say slow 'as in the time it takes to disappear from the outbox'
that is in fact your MUA or client talking whatever protocol (POP/IMAP)
to your MTA (server). From what I have observed, the qmail logs wont
show receipt of the email until its actually out of your outbox and on
its journey. From there it will talk SMTP server to server.
Im not sure of your setup - but do you have authentication turned on for
outbound? as in could it be a slow authentication issue? To test the
qmail servers speed, I would ssh into your server with 2 sessions. Do a
'tail -f /var/log/qmail/current' on one session and in the other send a
command line email 'mail [EMAIL PROTECTED]'. Take note from the
time you send this to the time it shows up in the logs - as in the
moment you press ^D to something displaying. It should be almost instant.
From your client, I would open another session, but this time 'tail -f'
your POP server or your IMAP server and see whats going on. I would
also install something like ethereal and see what was happening in terms
of communications - so you can see if the client initiates, and the
server takes a while to respond - and so on.
Another thing I just thought of: Is your server trying to do some sort
of reverse DNS lookup? Depending if it is or not and you have your DNS
server not configured for your clients, it couldbe doing some sort of
lookup timeout.
Most common setups go::
client -> POP/IMAP(maybe a lookup to your LDAP server here as well-
depending upon auth) -> qmail -> world
Break it down into its individual components and time trial each one in
order. Ethereal should be able to help you out a lot here. There is
plenty of information out there in the wild on how to drive it if you
are unsure. You should get some leads to work from.
Hope this helps
Darren
