Mailing List Archive

pete@more.net wrote:
>
> I'm running a mod_backhand server to redirect connections to 2
> mailservers. It is supposed to removeSelf and does until on of the
> backend servers goes down. Immediately it tries to serve pages from
> itself. Has anyone seen this problem before?

If mod_bakchand has trouble connecting (to proxy) to both servers, it could
fail in this way (it will tr to service the page locally). However, I see in
your configuration you are using HTTPRedirectToName. This causes mod_bakchand
to issue 302's instead of proxying the requests back -- so, it will never fail
in this fashion under your configuration as it doesn't attempt to make
connections for proxying.

> My mod_backhand settings in httpd.conf on the mod_backhand box are:
>
>
> <IfModule mod_backhand.c>
> UnixSocketDir /usr/local/apache/backhand
> MulticastStats 192.168.0.255:4445,1
> AcceptStats 192.168.0.0/24
> </IfModule>
>
>
> <Directory "/usr/local/apache/www">
> Options Indexes FollowSymLinks MultiViews
> Order allow,deny
> Allow from all
> Backhand removeSelf
> Backhand byAge 6
> Backhand byRandom
> Backhand byLogWindow
> Backhand byLoad
> Backhand HTTPRedirectToName
> </Directory>

You have two backend boxes. Don't use byRandom/byLogWindow. With two servers
it makes byLoad do nothing as their will only one of them left by the time
byLoad is processed.

Try:
Backhand byAge 6
Backhand removeSelf
Backhand byLoad
Backhand HTTPRedirectToName

>
> The mail servers have this in their apache config:
>
> <IfModule mod_backhand.c>
> UnixSocketDir /usr/local/apache/backhand
> MulticastStats 192.168.0.XXX:4445,1

192.168.0.XXX is needs to be a broadcast address... So, XXX should be 255 on
all your machines. Also, you don't need the trailing ,1 as that isn't a
multicast address (it is a normal broadcast address)

> AcceptStats 192.168.0.0/24
> </IfModule>
>
>
> Where XXX is the ip of the machine running as the mod_backhand server.


--
Theo Schlossnagle
Principal Consultant
OmniTI Computer Consulting, Inc. -- http://www.omniti.com/
Phone: +1 410 872 4910 x201 Fax: +1 410 872 4911
1024D/82844984/95FD 30F1 489E 4613 F22E 491A 7E88 364C 8284 4984
2047R/33131B65/71 F7 95 64 49 76 5D BA 3D 90 B9 9F BE 27 24 E7

That fixed it, thanks!


Pet

On Thu, Jun 26, 2003 at 01:33:20PM -0400, Theo E. Schlossnagle wrote:
> pete@more.net wrote:
> >
> >I'm running a mod_backhand server to redirect connections to 2
> >mailservers. It is supposed to removeSelf and does until on of the
> >backend servers goes down. Immediately it tries to serve pages from
> >itself. Has anyone seen this problem before?
>
> If mod_bakchand has trouble connecting (to proxy) to both servers, it could
> fail in this way (it will tr to service the page locally). However, I see
> in your configuration you are using HTTPRedirectToName. This causes
> mod_bakchand to issue 302's instead of proxying the requests back -- so, it
> will never fail in this fashion under your configuration as it doesn't
> attempt to make connections for proxying.
>
> >My mod_backhand settings in httpd.conf on the mod_backhand box are:
> >
> >
> ><IfModule mod_backhand.c>
> > UnixSocketDir /usr/local/apache/backhand
> > MulticastStats 192.168.0.255:4445,1
> > AcceptStats 192.168.0.0/24
> ></IfModule>
> >
> >
> ><Directory "/usr/local/apache/www">
> > Options Indexes FollowSymLinks MultiViews
> > Order allow,deny
> > Allow from all
> > Backhand removeSelf
> > Backhand byAge 6
> > Backhand byRandom
> > Backhand byLogWindow
> > Backhand byLoad
> > Backhand HTTPRedirectToName
> ></Directory>
>
> You have two backend boxes. Don't use byRandom/byLogWindow. With two
> servers it makes byLoad do nothing as their will only one of them left by
> the time byLoad is processed.
>
> Try:
> Backhand byAge 6
> Backhand removeSelf
> Backhand byLoad
> Backhand HTTPRedirectToName
>
> >
> >The mail servers have this in their apache config:
> >
> ><IfModule mod_backhand.c>
> > UnixSocketDir /usr/local/apache/backhand
> > MulticastStats 192.168.0.XXX:4445,1
>
> 192.168.0.XXX is needs to be a broadcast address... So, XXX should be 255
> on all your machines. Also, you don't need the trailing ,1 as that isn't a
> multicast address (it is a normal broadcast address)
>
> > AcceptStats 192.168.0.0/24
> ></IfModule>
> >
> >
> >Where XXX is the ip of the machine running as the mod_backhand server.
>
>
> --
> Theo Schlossnagle
> Principal Consultant
> OmniTI Computer Consulting, Inc. -- http://www.omniti.com/
> Phone: +1 410 872 4910 x201 Fax: +1 410 872 4911
> 1024D/82844984/95FD 30F1 489E 4613 F22E 491A 7E88 364C 8284 4984
> 2047R/33131B65/71 F7 95 64 49 76 5D BA 3D 90 B9 9F BE 27 24 E7
>
>
> _______________________________________________
> backhand-users mailing list
> backhand-users@lists.backhand.org
> http://lists.backhand.org/mailman/listinfo/backhand-users
>

--
Pete Greenwell
System Administrator
Missouri Research and Education Network [MOREnet]
http://www.more.net