Mailing List Archive

[mod_backhand-users] redirection problem
We've recently added a new server to a cluster of webservers. The old
servers are using mod_backhand v1.1.0, and the new server is using v1.20.

We have a very strange setup in which a dual redirect takes place; this
was necessary at the time in order to load-balance, but then subsequently
maintain state for an SSL session. The new bySession directive may
simplify this, but for now, we want to bring new servers into the cluster
one at a time, seamlessly. Trouble is, using the same httpd.conf generates
different behavior. These are our virtual host settings on the old servers
(IP addresses and hostnames changed to protect the innocent), in the order
they appear in the file:

NameVirtualHost 10.0.0.1

<VirtualHost 10.0.0.1>
ServerName www.test1.com
DocumentRoot "/opt/local/httpd/www/htdocs"
</VirtualHost>

<VirtualHost 10.0.0.1>
ServerName www.test.com
DocumentRoot "/opt/local/httpd/www/htdocs/redirect"
##BackhandSelfRedirect On
<Directory "/opt/local/httpd/www/htdocs/redirect">
Backhand byAge
Backhand byRandom
Backhand byLogWindow
Backhand byCost
</Directory>
</VirtualHost>

<VirtualHost _default_:443>
# General setup for the virtual host
DocumentRoot "/opt/local/httpd/www/htdocs"
(additional SSL directives)
</VirtualHost

So basically, requests coming into www.test.com (which is a DNS
round-robin entry itself, for further redundancy) get sent to the
"redirect" directory and get redirected by Backhand. The redirect
directory itself contains an index.html which executes an http redirect to
a page on the same server via https.

These virtual host settings produce the following listing in the
/backhand/ status page:

Entry Hostname Age Address etc.
0 www.test1.com 0 10.0.0.1:80 etc.
0 www.test2.com 0 10.0.0.2:80 etc.
(more servers follow)

and everything works great, but when we add the server using mod_backhand
1.2.0 to this cluster, the entry for it reads:

0 www.test3.com 0 10.0.0.2:443 etc.

The net result is that backhand redirects properly, but tries to send an
http request to port 443, the https port, producing an error.

Does anyone have any ideas on how I can get backhand to think it needs to
redirect to port 80 instead of 443 on this particular server? I've played
with nearly every possible combination of virtual host settings, and it's
unclear to me where backhand is pulling the 443 from, since the Backhand
directives aren't inside the SSL virtual host container. What am I
missing?

Thanks-

James Ervin
UNC-Chapel Hill
[mod_backhand-users] redirection problem [ In reply to ]
On Friday, October 5, 2001, at 04:24 PM, James Ervin wrote:
> The net result is that backhand redirects properly, but tries to send an
> http request to port 443, the https port, producing an error.
>
> Does anyone have any ideas on how I can get backhand to think it needs
> to
> redirect to port 80 instead of 443 on this particular server? I've
> played
> with nearly every possible combination of virtual host settings, and
> it's
> unclear to me where backhand is pulling the 443 from, since the Backhand
> directives aren't inside the SSL virtual host container. What am I
> missing?

Are you, by any chance, running a different version of Apache?
mod_backhand pulls the port out of the Listen directives. I assume you
have, in your conf file, something likst:
Listen 80
Listen 443

Try swapping them. You can always explicitly tell mod_backhand what IP
and port you want to advertise with the two argument version of the
MulticastStats directive -- see the online FAQ.

You should upgrade all your machines to 1.2.0 :-) Actually, 1.2.1 is
almost ready, and it has some nice features...

--
Theo Schlossnagle
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
[mod_backhand-users] redirection problem [ In reply to ]
Curses... I thought of swapping the Listen directives and thought I had
already tried it but aparently forgot to hit :wq!. That did the
trick. Thanks very much. The Apache version we're using did change, by the
way, from 1.3.14 to 1.3.20.

We'll be upgrading the rest of these servers after the weekend--we plan to
collect some performance statstics for a few days, since mod_backhand
wasn't the only thing we've changed; this new server is an almost complete
overhaul of the application in question.

Thanks again! I'll keep an eye out for 1.2.1. Is there a preview of the
release notes available anywhere?

James Ervin
UNC-Chapel Hill

On Fri, 5 Oct 2001, Theo Schlossnagle wrote:

> Are you, by any chance, running a different version of Apache?
> mod_backhand pulls the port out of the Listen directives. I assume you
> have, in your conf file, something likst:
> Listen 80
> Listen 443
>
> Try swapping them. You can always explicitly tell mod_backhand what IP
> and port you want to advertise with the two argument version of the
> MulticastStats directive -- see the online FAQ.
>
> You should upgrade all your machines to 1.2.0 :-) Actually, 1.2.1 is
> almost ready, and it has some nice features...
>
> --
> Theo Schlossnagle
> 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
>
[mod_backhand-users] redirection problem [ In reply to ]
On Friday, October 5, 2001, at 04:56 PM, James Ervin wrote:
> Thanks again! I'll keep an eye out for 1.2.1. Is there a preview of the
> release notes available anywhere?

As it isn't released... no. But you can see the differences between the
current version in CVS and the last tagged release.

http://commedia.cnds.jhu.edu/cgi-
bin/viewcvs/jesus/mod_backhand/ChangeLog.diff?r1=1.39&r2=1.36

The changes of content are at the bottom.

--
Theo Schlossnagle
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
[mod_backhand-users] redirection problem [ In reply to ]
> We'll be upgrading the rest of these servers after the weekend--we plan to
> collect some performance statstics for a few days, since mod_backhand
> wasn't the only thing we've changed; this new server is an almost complete
> overhaul of the application in question.

Heads up, Apache 1.3.21 is coming out either tonight, or tomorrow
sometime with a few UNIX fixes in there.

> Thanks again! I'll keep an eye out for 1.2.1. Is there a preview of the
> release notes available anywhere?

Do you have CVS access? You can look in the change log...

http://commedia.cnds.jhu.edu/cgi-bin/viewcvs/jesus/mod_backhand/ChangeLog.diff?r1=1.39&r2=1.36

-sc

--
Sean Chittenden