Mailing List Archive

Page cannot be found error
Good Day list members,
I am having a problem that perhaps someone here may be able to shed some
light on. I am having a strange inconsistent problem with backhand. It
appears that backhand does work sometimes, but sometimes it does not. I have
done some troubleshooting on this, and have narrowed down when it happens.

I have setup dns as follows
backhand-test.googlefish.com points to 192.168.2.191

setup:
platform solaris 8

I have three servers I am wishing to install backhand on.
comp1 ip 192.168.2.191
comp2 ip 192.168.2.192
comp3 ip 192.168.2.193

http://backhand-test.googlefish.com/backhand/ shows all 3 servers
correctly.

whenever you visit my website the docroot is not backhanded in the
configuration I have described below, but sometimes I have set it up that
way and the same problem occurs.

when I refresh or revisit the website
http://backhand-test.googlefish.com/app/ I can see that the page I have
stuck in this directory index.html is sometimes presented and sometimes the
page cannot be found. each index.html is unique on each server for testing,
so I am able to see this one url going to comp2 and comp3 and occasionally
comp1. However, occasionally it pulls up a page cannot be found message. I
have checked the logs on comp1 and found the following:

[Tue Oct 8 10:38:00 2002] [error] [client 192.168.2.47] File does not
exist: /app/index.html
[Tue Oct 8 10:38:21 2002] [error] [client 192.168.2.47] File does not
exist: /app/index.html
[Tue Oct 8 10:39:54 2002] [error] [client 192.168.2.47] File does not
exist: /app/index.html
[Tue Oct 8 10:39:55 2002] [error] [client 192.168.2.47] File does not
exist: /app/index.html

I even created an apache alias for the app directory and receive the same.


I changed the dns name at that point since it seemed to only happen on
192.168.2.191 (the ip that the backhand-test.googlefish.com name resolves
to). I changed the ip to 192.168.2.192 so that backhand-test.googlefish.com
now resolves to 192.168.2.192. I restarted apache on all the servers, and I
began to test again.

I got the same errors as before, but this time I received the errors on
comp2 (192.168.2.192). So it appears to me that somehow the error and where
the dns is pointed is related. Perhaps it is trying to proxy itself?? At
this point, I am a bit confused as to why this is occurring, and was hoping
perhaps a knowledgeable person in the group may be able to shed some light
on the subject.

--Manuel Arroyo


I configure and install backhand via the following
# cd mod_backhand-1.2.1
# ./precompile ../apache_1.3.26/
# cd ../apache_1.3.26/
# ./configure --prefix=/usr/local/apache \
--enable-module=most \
--enable-shared=max \
--enable-module=backhand --enable-shared=backhand
# make
# make install

httpd.conf shows the following:

<IfModule mod_backhand.c>
# UnixSocketDir is were the mod_backhand-Arriba file is stored
# (how fast your machine is) This directory must be readable and writable
# by euid of apache (nobody) Becuase the children have dropped privledges
# before they connect to UNIX domain socket in this directory.
# This directive is singular.
#
# MulticastStats of the form [<IP ADDR>] <BROADCAST ADDR>:<PORT> will set
# mod_backhand to broadcast server statistics on that address advertising
# for a server on <IP ADDR> or gethostbyname(gethostname())
# MulticastStats of the form [<IP ADDR>] <MULTICAST ADDR>:<PORT>,<ttl> will
# set mod_backhand to multicast server statistics on that address
# advertising for a server on <IP ADDR> or gethostbyname(gethostname())
# This directive is singular.
#
# AcceptStats <a.b.c.d>[/<mask>] (like 10.0.0.4 or 10.0.0.0/24) will accept
# statistics originating from that IP or IP network.
# This option can be cascaded.

UnixSocketDir /usr/local/apache/backhand
# MulticastStats 128.220.221.255:4445
MulticastStats 225.220.221.20:4445,1
# AcceptStats 128.220.221.0/24
AcceptStats 192.168.2.0/24

# This is a status of sorts. Visit it and see how valuable it is to you.
<Location "/backhand/">
SetHandler backhand-handler
</Location>
</IfModule>

and I have the following virtual host setup

<VirtualHost *:80>
ServerAdmin marroyo@x25.net
DocumentRoot /webroot/backhand-test.googlefish.com
ServerName backhand-test.googlefish.com
ErrorLog logs/backhand-test.googlefish.com-error_log
CustomLog logs/backhand-test.googlefish.com-access_log combined
DirectoryIndex index.html index.php3 index.htm index.phtml index.php
AccessFileName .htaccess

<Directory /webroot/backhand-test.googlefish.com>
#Options Indexes
Options None
AllowOverride All
Order deny,allow
Deny from all
Allow from all
</Directory>

Alias /app/ /webroot/backhand-test.googlefish.com/app/
<Directory /webroot/backhand-test.googlefish.com/app/>
Options None
AllowOverride All
Order deny,allow
Deny from all
Allow from all
Backhand byAge
Backhand byRandom
Backhand byLogWindow
Backhand byLoad
</Directory>
</VirtualHost>


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Page cannot be found error [ In reply to ]
On Tuesday, Oct 8, 2002, at 12:38 US/Eastern, Arroyo, Manuel wrote:
>
> [Tue Oct 8 10:38:00 2002] [error] [client 192.168.2.47] File does not
> exist: /app/index.html
> [Tue Oct 8 10:38:21 2002] [error] [client 192.168.2.47] File does not
> exist: /app/index.html
> [Tue Oct 8 10:39:54 2002] [error] [client 192.168.2.47] File does not
> exist: /app/index.html
> [Tue Oct 8 10:39:55 2002] [error] [client 192.168.2.47] File does not
> exist: /app/index.html

This may be fixed the by the patch I just posted to the list.

--
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

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