Linux System Admins Blog

APC (Alternative PHP Cache) is a free, open, and robust framework for caching and optimizing PHP intermediate code. APC is a great tool to speed up a php driven site and I can’t even think of a big site running on a php framework without an opcode cache (other good choices are eaccelerator or xcache). [...]

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I made a copy of Drupal6 site with SecurePages module installed and configured. This module is configured to redirect all or certain pages to https – depending on your configurations. For our setup we usually include the login and admin sections to redirect to https.
The problem is on the copied site that is [...]

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Although we made it a standard not to make any changes to Drupal core and core modules, there are times that our developers really need to make changes to core modules in order to add the required functionality. Cases like additional feature for ‘user’ or ‘comment’ modules and so on. At this state [...]

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Absolute Path Error:
cvs [checkout aborted]: absolute pathnames invalid for server (specified `/path/drupalsite/’)
Ok, I got the error above when I performed Drupal CVS update on our Debian server (newly installed CVS 1.12.13). The same command works on other server with older CVS installation. The issue is the reference to local cvs directory [...]

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Typically Squid caching proxy server listen and outgoing IP address are the same. Sometimes, for various reasons we want to alter the outgoing IP address. The new address must first be brought up as an interface on the squid server. In squid.conf look for tcp_outgoing_address line, uncomment it and replace the default IP value with [...]

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If you are using a shared server, or just have a limited account on your company servers, you might not have access to your php configuration file php.ini (this is usually found under /etc/php.ini in rhel/centos and /etc/php5/apache2/php.ini in debian/ubuntu). Still, in many situations it might be needed to enable php errors in the browser [...]

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This quick post will show how we can easily allow only certain http referrers see some location using nginx. This might be useful for example if you are using nginx as a static content provider and want to not allow everyone hot-linking your images and only your own sites. Doing something like this in nginx [...]

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Many people use subversion over ssh for a simple and secure way to work on remotely hosted svn repositories. This is normally as simple as running:
svn co svn+ssh://user@server/repo .
If the remote ssh server is not running on the default ssh port (tcp 22) then this needs a little tweaking to get it working. Normally I [...]

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This guide will help you setup Nagios user to have limited access to host and service checks. It is helpful when you want to allow your customers or clients to view and receive alerts on their servers and services, like for dedicated servers.
Procedure:
Contacts: Create new contact definitions for your client.
[...]

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