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

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

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

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Commands & Shells

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

Script to Verify Passwordless SSH Access

September 19, 2013 – 1:33 pm
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If you have passwordless SSH configured on multiple servers, it’s a good idea to verify your access from time to time. This task may get rather tedious with a large number of remote systems. The simple script below will cycle through a list of servers and make sure you can access them without being prompted for a password. Any failures will be saved in the CSV file for later analysis.

Celerra NFS/CIFS Mixed Permissions Mode

September 17, 2013 – 11:21 am
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This is a quick reminder on how to configure a Celerra filesystem for dual NFS/CIFS access where Windows-side permissions would translate correctly to the NFS side. By default, Celerra datamover will mount filesystems in “Native” mode. In this case, a file or folder created by a Windows user via the CIFS share will take on the default Unix permissions on the NFS side: 755 for folders and 644 for files.

Configure Anonymous FTP on Solaris 10

August 25, 2013 – 2:30 pm
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Below are basic steps for configuring anonymous FTP service on Solaris 10. Use with caution.

Enable Basic FTP Server on Solaris 10

August 22, 2013 – 2:22 pm
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Here are a few simple steps to enable a basic FTP server on Solaris 10.

Simple Network Discovery

August 21, 2013 – 11:38 am
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The bash script below will scan the specified IP range and use dig and nmap to try to determine the fully-qualified domain name, type and the operating environment of any device that responds to network …

Basic Samba Configuration on Solaris 10

August 20, 2013 – 2:21 pm
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Here’s a sample process for installing and configuring a basic Samba server on Solaris 10.

Solaris 10 NFS Server Configuration

August 16, 2013 – 2:01 pm
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As far as NFS servers go, I think the best platform in terms of performance and stability is Solaris running on SPARC architecture. Perhaps this has something to do with the fact that NFS was created for Solaris. Over the years I’ve been working with NFS servers on AIX, HP-UX, Linux, BSD, etc. It always worked better on Solaris.

RPC: Authentication When Mounting Solaris NFS Share

August 16, 2013 – 1:37 pm
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When mounting an NFS share from a Solaris 10 server, you may encounter the “RPC: Authentication” error. You may notice that you are able to mount the share via NFSv4, not not NFSv3. On the NFS server the /var/adm/messages may show the following errors for the client…

Dealing with Full Filesystems

June 25, 2013 – 11:03 am
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Filled up filesystems is a recurring condition eating up sysadmin time on a regular basis. Some studies show that filesystems running out of space are responsible for most day-to-day issues handled by IT departments. Disk …

Friday – Healthy Lifestyle

June 21, 2013 – 7:16 pm
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I always had a hard time explaining to non-tekkies what I do for living. Well, today I heard the best ever description of my job. You know the guy who walks behind a circus elephant with a large bag? In my case the elephants are made by HP, IBM, and EMC.

Quickly Grow EMC Celerra Filesystem

June 21, 2013 – 11:22 am
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As we all know, Celerra and its kin can get a bit annoying with their “filesystem over 90%” warning emails. Enabling the “autoextend” feature for the filesystems is one option, but if you are a control …

Watch the Log

June 18, 2013 – 8:06 pm
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In the past few days my Postfix server has been having occasional problems talking to the mail gateway. They problem would come and go. The Postfix server would timeout trying to connect to the gateway and keep …

Bash scripting: lists and random things

April 16, 2013 – 12:39 pm
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Imagine you have an HPC cluster with a hundred compute nodes named node001-node100. The two commands below will help you generate a list of node names – either all name on one line or one name per …

iPhone Stopped Syncing with Google Calendar

April 3, 2013 – 3:05 pm
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A small but potentially annoying problem: on rare occasions, your iPhone/iPad may decide your calendar looks full enough and will stop syncing with your Google calendar. This is a situation where:

Calendar sync between your iDevice and …

Install Pflogsumm PostFix Log Summarizer

March 12, 2013 – 9:58 am
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Pflogsumm is yet another log analyzer/summarizer for Postfix. It is written in Perl and has been around for a while. Very simple to install, so I writing this post mostly as a note to myself. I added an example cron job with some “grep” syntax to cut the Pflogsumm report down to size by dropping some things I am usually not interested in.

Installing Sendmail Analyzer on RHEL/CentOS

March 11, 2013 – 11:35 pm
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The Sendmail Analyzer can be useful for visualizing your Sendmail/Postfix log. The commands below can be copy-pasted as root on default installations of RHEL and CentOS 5/6 with default Postfix and httpd. If your configuration …

Fast IP Range Scanner in Bash

February 22, 2013 – 2:53 pm
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Just a simple script to scan an IP range and do a reverse DNS lookup. This can be useful for building an inventory of systems on your LAN. Just make sure to give your network …

openlava Quick Test

February 22, 2013 – 12:46 pm
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After years working with PBS and LSF, ran into Jeff Layton’s “Share the Load” review of openlava resource manager in the Feb 2013 issue of the Admin Magazine and nostalgia took over. So I built …

Secure Data Destruction for Unix

February 21, 2013 – 11:45 pm

What is secure computer data destruction? Simply put, securely-deleted data cannot be recovered by any known technique. But when it comes to data security, things are rarely simple. New data recovery methods are developed every …

SEO for Unix Geeks

February 21, 2013 – 11:45 pm
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So, you are finally done with your new shiny Web site and looking for ecom site integration. Congratulations. There is one small problem: the only two visitors to the site are you and Googlebot. And …

Selecting CMS Software

February 21, 2013 – 11:45 pm
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If you are looking for an open-source content management system, your choices are likely to boil down to these three: Joomla!, WordPress, and Drupal. Professional CMS developers tend to disregard WordPress as a purely blogging …

Protected: KW MSP-10X Prototype

February 21, 2013 – 11:45 pm

There is no excerpt because this is a protected post.