Apache 500 error with no entries in error.log

Question

This is on a brand new Ubuntu 14.04 Server running a standard WAMP install with Apache DAV_SVN (using LDAP Authentication) added on top of it (mapped to /svn). I was able to get everything working correctly, and tested accessing subversion via HTTP and authenticating via LDAP and had no issues.

Then, I went into /etc/network/interfaces and changed it from DHCP to use a static IP address (so the DNS server can resolve the hostname for SVN). I performed a reboot on the server, and afterwards any attempt to access /svn result in a 500 error (AFTER providing ldap authentication credentials) - however accessing just / returns the default apache page correctly.

However, there is no record of a 500 error in error.log, so I have no way to debug what the error is. I'm not sure if the error is with communicating the credentials to LDAP, with SVN, Apache or what.

---

Update

I was able to confirm that going back to DHCP allows SVN to work again, however I need a static IP so I can use hostname routing for SVN - using a dynamic IP for a repository will create a management mess.

error.log

[Fri Feb 06 10:17:37.915182 2015] [mpm_prefork:notice] [pid 1090] AH00163: Apache/2.4.7 (Ubuntu) PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 10:17:37.915260 2015] [core:notice] [pid 1090] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 10:19:45.681937 2015] [mpm_prefork:notice] [pid 1090] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 10:19:46.786369 2015] [mpm_prefork:notice] [pid 1987] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 10:19:46.786434 2015] [core:notice] [pid 1987] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 10:19:48.285095 2015] [mpm_prefork:notice] [pid 1987] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 10:19:49.398153 2015] [mpm_prefork:notice] [pid 2074] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 10:19:49.398214 2015] [core:notice] [pid 2074] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 10:41:45.351303 2015] [mpm_prefork:notice] [pid 2074] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 10:41:46.517131 2015] [mpm_prefork:notice] [pid 3665] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 10:41:46.517209 2015] [core:notice] [pid 3665] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 10:42:41.050821 2015] [dav:error] [pid 3669] [client 192.168.12.162:59312] Could not fetch resource information.  [301, #0]
[Fri Feb 06 10:42:41.050932 2015] [dav:error] [pid 3669] [client 192.168.12.162:59312] Requests for a collection must have a trailing slash on the URI.  [301, #175002]
[Fri Feb 06 10:46:13.366128 2015] [mpm_prefork:notice] [pid 3665] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 10:46:14.514782 2015] [mpm_prefork:notice] [pid 3738] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 10:46:14.514837 2015] [core:notice] [pid 3738] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 10:56:37.258172 2015] [mpm_prefork:notice] [pid 3738] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 11:09:35.552252 2015] [mpm_prefork:notice] [pid 1526] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 11:09:35.558499 2015] [core:notice] [pid 1526] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 11:21:48.478383 2015] [mpm_prefork:notice] [pid 1526] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 11:22:06.006478 2015] [mpm_prefork:notice] [pid 1067] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 11:22:06.007231 2015] [core:notice] [pid 1067] AH00094: Command line: '/usr/sbin/apache2'
[Fri Feb 06 11:41:32.208255 2015] [mpm_prefork:notice] [pid 1067] AH00169: caught SIGTERM, shutting down
[Fri Feb 06 11:41:33.396579 2015] [mpm_prefork:notice] [pid 1392] AH00163: Apache/2.4.7 (Ubuntu) SVN/1.8.8 PHP/5.5.9-1ubuntu4.3 configured -- resuming normal operations
[Fri Feb 06 11:41:33.396643 2015] [core:notice] [pid 1392] AH00094: Command line: '/usr/sbin/apache2'

Solution 1

Just want to follow up and post what the issue and resolution was. Basically the issue was that I didn't assign a local DNS server when I setup the static IP, so it wasn't resolving the LDAP server hostname. When it was setup for DHCP it was using DNS assigned by the DHCP just fine. The solution was just to add the local DNS servers into /etc/network/interfaces, after that everything worked correctly.

I'm still not sure why there was no error log entry produced for this.

Solution 2

There has been a similar question to yours already posted on Stackoverflow:

Internal Error 500 Apache

Firstly, as you have shown your port is alive and accepting users, however navigating to a subdirectory doesn't work.

I faced a similar issue on CentOS whereby the root worked http://somesite.com but when I went to http://somesite.com/xyz, it gave me a 500 error.

This was caused by a lack of permissions on the /xyz folder and that the .htaccess/httpd.conf file was not properly setup with:

<VirtualHost :80>
...
Insert your permissions here
</VirtualHost>

Or alternatively (provided you don't want public access to this and limit it to an IP of your choosing):

<Directory /xyz>
Options Follow Symlinks
Order deny, allow # If you want it to be public, use Order Allow, Deny; and
Deny from all #Allow from all
Allow from {IP of your choosing} #If Allow from all is present, this is line is not necessary. 
</Directory>

Mess around with your httpd.conf/.htaccess file, it's a permissions issue. :)

EDIT:

Also, make sure that if you use a database to serve content on /xyz, that the credentials the backend .php uses are correct, a database error can be hidden from the public view with a 500 internal error. (An easy way to check this is to: apt-get install lynx and then issue lynx http://127.0.0.1/svn)

Comments

[user9517]

Are there any other logs configured that may have errors in ?

[PaulDavis]

@Iain - I only have the above mentioned services that I setup on this machine (being brand new). Do you have any ideas of where other logs would be, there's nothing of interest in /var/log as far as I can tell.