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Re: Bizarre problem

To: "LinuxVirtualServer.org users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: Bizarre problem
From: Joseph Mack NA3T <jmack@xxxxxxxx>
Date: Fri, 26 May 2006 10:47:53 -0700 (PDT)
On Fri, 26 May 2006, John Oliver wrote:

OK, I have LVS-DR set up.  From another host on the same subnet as the
director, I can connect to port 80 of the VIP with telnet and see a
response from one realserver, then the other.  All is well, right?
Wrong!  From browsers, I always get a response from one realserver.
Shift-reloads do not make it change.

This may not be a problem. I've had setups where when you fetch a page and all its gifs etc, you find the hits came evenly from all the realservers (eg each realserver was responsible for about the same number of gifs). Then I've had setups that behaved the way yours does. I don't know whether its the client or the apached, different versions of LVS, or what.

Somewhere in the HOWTO there is a writeup of how clients can maintain a connection, so subsequent requests for hits aren't seen as a new connection. This may account for it.
I don't know myself.

No, there is no proxy server,
Squid, cache, etc.

I'm looking for a log file or something that shows what IPVS is doing in
realtime to help troubleshoot this.  Just running ipvsadm isn't
helping... it always shows:

[root@quark ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
 -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.101.82:http rr
 -> 192.168.101.81:http          Route   1      0          0
 -> 192.168.101.80:http          Route   1      0          0

this is because the webserver is shutting down the connection after sending the hit.

I installed telnetd on both realservers and configured LVS to do that,
and it works perfectly.  I'm really stumped here... all indications are
that LVS is working correctly, but I always get a response from one
realserver when trying a test web page.  What can I do to figure this
out?

I would say you're OK so far. You're only using one client? Can you try it with two?

Joe
--
Joseph Mack NA3T EME(B,D), FM05lw North Carolina
jmack (at) wm7d (dot) net - azimuthal equidistant map
generator at http://www.wm7d.net/azproj.shtml Homepage http://www.austintek.com/ It's GNU/Linux!

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