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IMDB Lookup Script

March 5, 2015 – 1:02 pm |

IMDB is one of the most complete movie and television databases on the Internet. It offers an advanced Web search UI, but Unix CLI support has been discontinued years ago and the old scripts no …

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Networking

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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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.

Commands & Shells »

Late Night Rant #26

March 30, 2015 – 12:30 am |

When you’ve ls’d, grepped, catted, piped and tailed everything on your computer and there is absolutely nothing left to do, there’s always this… Read the full story »

Login Monitor

March 6, 2015 – 12:02 am |

Sometimes after a couple of beers I start feeling paranoid. I make sure the door is locked and check my firewall logs. Here’s a very basic script to monitor your server’s login record and notify you about …

Installing Salt Minion on RHEL5

February 19, 2015 – 10:38 am |

As of recently, python26-distribute has been removed from EPEL5 due to lack of support and attempting to install salt-minion on RHEL5 will throw a dependency error. If you are still running RHEL5, you would need …

Late Night Rant #25b

February 17, 2015 – 5:41 pm |

No sooner than I stopped complaining about HP’s “holy” Web site, I ran into a similar issue with Red Hat’s site. And that doesn’t happen very often. Unlike HP, Red Hat folks tend to take better …

Late Night Rant #25: HP’s Web Site Fail

February 12, 2015 – 6:24 pm |

I’ve already mentioned my dislike for the epic mess of broken links HP gingerly called its Web site. Nearly a year-and-a-half later the situation did not improve. Actually, it might have gotten worse.

Memory Utilization-by-User

February 10, 2015 – 5:13 pm |

Here’s a useful one-liner (sort of) that will show you memory utilization details by user ID on Linux (RHEL, Fedora, CentOS) systems. This may come in handy when trying to figure out who is eating …

Late Night Rant #24: North Korean Internet

December 22, 2014 – 8:05 pm |

Today was the day the North Koreans would have learned they had the Internet and the Americans DDOSed it. Unfortunately, they had no Internet, poor bastards. But, as long as this keeps us entertained… Hey, …

Late Night Rant #23: Kim The Sony-Slayer

December 17, 2014 – 10:09 pm |

Sony execs are shedding crocodile tears over the latest IT security breach that brought substantial financial losses to the company. Let’s not dwell on the trivial: who did it and why are irrelevant technicalities. How …

RHEL/CentOS Yum Operations

December 14, 2014 – 11:42 pm |

The Yellowdog Updater, Modified has more features than most of us will ever need. Below are some hopefully useful examples that will help keep your system maybe secure by replacing old known bugs with new …

Using Pflogsumm Postfix Log Analyzer

December 4, 2014 – 12:29 am |

Pflogsumm is an oldie but a goodie. It’s a Perl script that sifts through your Postfix server maillog and provides you with a neat summary of events and some statistics. This information can be useful …

Visualizing Apache Logs with Logstalgia

December 4, 2014 – 12:01 am |

The Logstalgia is a cool graphical utility for visualizing the Apache access_log files. The practical value of Logstalgia is debatable, but it’s entertainment value is not in question. The managers and NOC operators can stare …

Sending Attachments Using Mailx

December 3, 2014 – 2:32 pm |

Sometimes it’s just better to attach a file to your email than to “cat” the contents into the email body. You will need the “uuencode” utility installed. On CentOS/RHEL you can install it by doing …

Fail2ban Whitelist IPs

December 2, 2014 – 9:16 pm |

Fail2ban is an excellent security tool that will do a good job safeguarding your server. However, using fail2ban you may run into two issues: friendly fire and inability to permanently ban hostile networks. I already …

Identifying Available IPs on the Network

December 2, 2014 – 2:31 pm |

At some point available IPs on your network may become few and hard to come by. Documentation becomes outdated and does not accurately reflect which IPs are still in use. A good starting point would …

Using truss and nawk to Trace Solaris Processes

November 18, 2014 – 1:54 pm |

Here’s the problem I ran into today on a Solaris 11 SPARC server: an application UI would occasionally freeze for a few second when executing a particular function. Nobody could quite figure out where the …

Adding Swap with Solaris 11 ZFS

October 22, 2014 – 4:24 pm |

With the swap partition residing on a ZFS filesystem, you have an easy way of adding swap on the fly. Reducing swap is not quite so simple, but we’l talk about that later. To check …

Enable NTP Client on Solaris 11

October 7, 2014 – 8:27 pm |

Just some quick instructions for configuring and enabling NTP client on Solaris 11.

PHP Unable to allocate memory for pool

September 9, 2014 – 10:57 pm |

The following error may be found in /var/log/httpd/${domain}/error_log when APC memory is set too low: “PHP Warning: require_once(): Unable to allocate memory for pool”. APC is Alternative PHP Cache. You can check the version of …

Getting Epoch Time on Solaris 10 and Older

September 8, 2014 – 3:57 pm |

You can get the epoch time on Solaris 11 and Linux simply by running the date command:

Installing GoAccess on CentOS/RHEL

June 24, 2014 – 11:02 am |

GoAccess is a simple but useful “top”-like CLI utility giving you a quick overview of the Apache access_log entries.

NTP Client Configuration on CentOS

May 15, 2014 – 8:31 pm |

Just some quick note on configuring NTP client on CentOS/RHEL/Fedora and forcing time update. Just got tired of having to remember these steps every time I run into NTP.

Searching Log Files

April 18, 2014 – 4:40 pm |

This is a quick example of finding the first and last occurrence of an event in the log file. This can be useful for determining the service outage window and for general troubleshooting. In the example below I am looking at the PostFix maillog file, trying to figure out the duration of the problem I’ve been having with one of the mail relay servers.

WordPress Remove Extra Line Breaks

December 2, 2013 – 3:09 pm |

Frequently, imported posts or posts created by auto-blogging plugins will create unnecessary tabs, newlines, and line breaks. This has a negative impact on readability and aesthetics of your site. If you cannot address the problem …