Author Archives: pingd

Pick random line from text file with bash and shuf.

So lets say you have a text file called list.txt with entries like: What if you wanted to pick a random entry? The easiest solution is to use the ‘shuf’ tool, which is standard on CentOS as part of coreutils. … Continue reading

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New ZFS on Linux release (RC9).

We have one of the most comprehensive guides on the internet for ZFS. Please check the updated guide for assistance with installing ZFS on Linux, specifically CentOS 6.2 here: Installing ZFS RAID-Z on CentOS 6.2 with SSD Caching

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No module named cElementTree yum update error

Found yum broken on a legacy CentOS 5.x server while installing updates. The error was: root # yum update There was a problem importing one of the Python modules required to run yum. The error leading to this problem was: … Continue reading

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Installing ZFS RAID-Z on CentOS 6.2 with SSD caching.

Updated August 16th, 2012 I recently had a project that required data storage with deduplication, data integrity assurance, and hardware fault tolerance. Instead of going with a traditional hardware RAID solution I opted to test out ZFS. My configuration utilized … Continue reading

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KVM Hardware Virtualization on CentOS 6.2 Dedicated Servers

I wrote this guide to show you how to do a proper KVM setup on your CentOS dedicated server. We will be using VNC and connecting to the dedicated server remotely from your workstation. I realize there are a lot … Continue reading

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List all installed Perl modules on server.

Sometimes you may need to figure out which Perl modules you have installed on your server. This can be very useful when cloning a server for a development project. The easiest way to see every installed module and the module’s … Continue reading

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Can’t remove or re-add a cPanel addon or parked domain?

Sometimes you may find that a domain just won’t go away from cPanel. You may be trying to simply remove an addon domain or a parked domain, or you may be trying to re-add a domain that was at some … Continue reading

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Download a backup over 2GB through cPanel instead of Apache.

Apache/FTP in some configurations can’t serve files that are over 2GB. This has been largely corrected on most HEL/CentOS cPanel servers, but there are legacy exceptions. There is a way to get such a large file via a cPanel function. … Continue reading

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Secondary Exim Port for cPanel and WHM.

Some ISPs block outbound connections to servers on port 25 for SMTP. This is becoming less common, but still occurs on smaller or foreign ISPs. The reason they block this port is to prevent compromised client computers, especially botnets, from … Continue reading

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See logged in users on CISCO IOS and disconnect them.

So you may want to see who else is accessing the switch or router that you’re on. Sometimes this is because you get a write error when trying to save the running config. The error would be something like: This … Continue reading

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