Bizarre problem

[Joseph Mack NA3T]

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 at 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
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