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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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Networking

Unix and Linux network configuration. Multiple network interfaces. Bridged NICs. High-availability network configurations.

Applications

Reviews of latest Unix and Linux software. Helpful tips for application support admins. Automating application support.

Data

Disk partitioning, filesystems, directories, and files. Volume management, logical volumes, HA filesystems. Backups and disaster recovery.

Monitoring

Distributed server monitoring. Server performance and capacity planning. Monitoring applications, network status and user activity.

Commands & Shells

Cool Unix shell commands and options. Command-line tools and application. Things every Unix sysadmin needs to know.

Dealing with ReiserFS bad blocks

March 24, 2008 – 6:42 pm
linux_penguin_0001

The following is a procedure for recovering a ReiserFS filesystem with bad blocks. If this is a system FS and cannot be unmounted, the box needs to be booted from the latest version of Knoppix …

ReiserFS Filesystem Recovery

March 21, 2008 – 3:55 pm
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The this is a description of a method for recovering ReiserFS filesystems from failed disks with bad blocks, when other recovery methods (reiserfsck) will not work. For this example, the failed server is called node1 …

Log Monitoring with Swatch

March 11, 2008 – 1:43 pm
binoculars watch security rifle gun

Swatch is a Perl-based log monitoring tool that can match regular expressions and perform automated actions. The tool is useful for monitoring system log files in real time with an option to run external commands …

Linux User Activity Management

March 9, 2008 – 2:59 pm
sniper soldier

The following is a detailed look into managing Linux users and the system resources they utilize. Disabling user access; halting, killing, and re-nicing user processes; controlling disk space allocation are all points covered by this …

Veritas Cluster Troubleshooting

February 27, 2008 – 1:26 am
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Veritas cluster server is a high availability server. This means that processes switch between servers when a server fails. All database processes are run through this server – and as such, this needs to run smoothly. Note that the oracle process should only actually be running on the server which is active.

Veritas HSM Maintenance

February 12, 2008 – 11:22 am
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When resizing a VXFS filesystem on a server that has HSM running, it is necessary to place HSM in maintenance mode for that particular filesystem. Failing to do so may cause the VFS resize operation …

Protected: SuSE Mail Transfer Agent Configuration

February 7, 2008 – 3:48 am

There is no excerpt because this is a protected post.

Korn Shell Arrays

January 24, 2008 – 11:13 am
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Here are a few useful examples of how to use data arrays within Korn shell. Arrays are a great tool for storing user input and other data for quick, on-the-fly access. If, for example, you …

A simple text string search script

December 13, 2007 – 1:52 pm
shell

Sometimes you need to locate a text string in various configuration files. You don’t know which files. You can just use “grep *”, but the output is rather messy and you can only search in …

Upgrade procedure for phpBB2

November 1, 2007 – 11:09 am
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The following is an example procedure for upgrading phpBB2 bulletin board software running under Linux. This procedure allows to retain forum customization.

Download “Changed files only” package from http://www.phpbb.com/downloads.php
Tar cvf and gzip the entire phpBB2 installation …

Linux performance tuning

August 22, 2007 – 2:40 pm
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Linux Performance Tuning
April | May 2007 | by Jaqui Lynch
Note: This is the second article in a two-part series. The first installment was published in the February/March issue.
In last issue’s article I introduced basic Linux* …

MySQL query cache

August 17, 2007 – 11:15 am
mysql

Query cache can significantly speed up database operations for identical search queries. This is particularly useful for Web server applications, where multiple requests for the same data are a regular occurrence.
To enable query caching on …

MySQL LOAD DATA Syntax

January 2, 2007 – 8:33 am
Bottlenose Dolphin (Tursiops truncatus) pod swimming over coral reef, Ogasawara Island, Japan

Using LOAD DATA LOCAL INFILE is a much faster way to insert lots of data into a table than using INSERT. The only preliminary step is to format the input file with unique field separators.
In …

Configuring eMule for Best Performance

December 27, 2006 – 12:22 am
emule_logo1

“eMule is a peer-to-peer file sharing application that works with both the eDonkey network and the Kad network. The distinguishing features of eMule are the direct exchange of
sources between client nodes, fast recovery of corrupted …

Creating table indexes in MySQL

November 21, 2006 – 6:32 pm
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Creating an index for specific columns in a database table can greatly speed up search operations. This is important for any database query that use WHERE in the SQL string. Below is a practical example …

Windows XP Desktop

November 20, 2006 – 12:34 am

A few screenshots of my Windows XP to supplement my collection of KDE and Sun Java Desktop screenshots.

Recovering from Veritas VEA GUI errors

October 31, 2006 – 11:18 am
di-logo-solaris-orange

Veritas Volume Manager GUI is more functional and intuitive that that of any other volume management application. However, once in a while the VEA GUI becomes corrupted and displays incorrect information. One of the symptoms …

Exceed session quits after login

September 29, 2006 – 12:05 pm
istock-18586699-monkey-computer

The following problem is encountered occasionally in most flavors of Unix and versions of Exceed. A user was able to use Exceed without problems to connect to the same Unix server just the other day. …

Contacting the sysadmin from command line

September 28, 2006 – 11:10 pm
colorful shells

If you are a sysadmin, communicating with your users is an important aspect of your job. Phone, e-mail, SMS, and various service request systems are commonly used by most businesses. The problem with all these …

The correct MySQL GRANT syntax

September 21, 2006 – 12:18 pm
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It is surprising how many people run into problems trying to use the GRANT command: everything from not being able to access a database table to losing admin access to MySQL altogether. There’s a bunch …

Palm TX: Review, Software, and Configuration

September 3, 2006 – 7:12 pm
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Recently I got a Palm TX and so far I like everything about it. Except for the $300 price tag. Built-in Wi-Fi card and a larger screen that can operate in landscape mode are the …

Changing time

May 11, 2006 – 12:12 am
time clock watch

Unix systems record several time parameters associated with files. Sometimes you might need to set time parameters on a file to a particular value. Or you might need to modify a file without changing any …