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March 2, 2022 – 2:00 pm

Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …

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Home » Archive by Month

Article Archive for October 2012

A Faster Way to Delete Many Folders

October 24, 2012 – 11:00 pm
shell

This issue is particularly annoying when dealing with expansive directory structures mounted via NFS. Let’s say you have a directory with ten thousand folders and each of them has more subfolders and files. And you …

Fixing the mount.nfs: rpc.statd is not running Error

October 22, 2012 – 4:11 pm
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The rpc.statd service is used by NFS client to help it recover from loss of connectivity to the NFS server. When rpc.statd is not running, NFS is not able to handle remote file locking. You …

System Recovery: Useful Tools

October 18, 2012 – 9:48 pm

The following is a brief collection of open-source and/or free tools I regularly use for various system recovery tasks. If the servers you work with have CD drives, I would recommend burning these images onto a CD or DVD. This would save you the trouble of messing with the boot options in the BIOS. More advanced versions of BIOS can mount remote ISO images and boot from those. In most cases, however, this approach requires using the dreaded Internet Explorer an requires Windows.

Dealing with Blank Lines in WordPress functions.php

October 17, 2012 – 1:06 am
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This is an annoying little problem plaguing many WordPress themes: blank lines in the themes’ functions.php cause various random issues. The most common manifestation of this condition is the failure to save the “image” custom field. Below are a few commands to apply a quick fix. Unfortunately, these steps would need to be repeated every time you upgrade your theme, until the developers catch on. To simplify this task, I arranged the commands into a little script that will create a backup of your original functions.php and make the necessary changes.

Searching Large Network-Mounted Filesystems

October 16, 2012 – 4:14 pm
shell

Recently I ran into a small problem: I needed to find recently-modified files in a very large NFS filesystem. One of the high-level folders contained dozens of sub-folders with thousands of files in each. There is a significant performance penalty associated with placing such directory structures on network-mounted filesystems. Running the “find” command at the top of the filesystem would have taken over an hour and the problem here was not available bandwidth, but the time it takes for the “find” to request and receive attribute information for each folder and file.

Simple Shell Random Password Generator

October 2, 2012 – 10:54 am
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A very simple script to generate a random secure password of desired length. This can come in handy when setting up multiple user account and/or lacking imagination.