We’ve run into problems remotely running some applications via X. Even when the app runs OK, it is quite sluggish. We also had trouble running in secondary X sessions, which is the default behavior of vncserver. Most apps acted just fine; however, some apps got confused about what desktop to use. We tried VNC, though, […]
Using a Full Desktop with VNC
A is for at
The at command is your willing and punctual servant for odd jobs, reminders and one-offs. A more footloose sibling of steadfast cron, at is used to schedule a task to run once at a given time. Then all is forgotten. The following examples and file paths are true for Red Hat Linux, and more or […]
B is for bash
Bash is a huge subject! The purpose of this article is demonstrate & explain some of the basics so you can write shell scripts and work at the command line more effectively. See also our article on Aliases and Functions in bash for ways to customize your environment. I recommend highly the bash man page!!! […]
C is for ch ch ch changes….
C is an extremely useful letter of the alphabet in Linux, especially when paired with an h. With these letters one can chown, chmod, chroot, and change lots of other things. One can even chkconfig. ***************************** chown – change ownership of a file. ***************************** Nothing too exciting to report here, but there are a couple […]
D is for df, du, dd
These three classic Unix utilities like to get their hands dirty with file systems. **************************************************** df – display disk space usage on mounted filesystems **************************************************** Every newbie sysadmin learns df right off the bat; it displays mounted file systems and the disk space usage on each. By default (in linux) it displays the statistics as […]
E is for Ext3fs Part 1
The ext3 filesystem now installs as the default file system in most Linux distributions. Essentially ext2 with journaling, ext3 retains the stability and robustness of ext2 while adding the much needed journal for high-availability. Part 1 of this article will discuss some filesystem basics and Part 2, some tips for working with the Linux native […]
E is for Ext3fs Part 2
In Part 1 of this article, we discussed some basics of the ext* filesystems in Linux. In this section we’ll have some good old filesystem fun. The most commonly used tools for working with Linux filesystems are mke2fs (create ext2/ext3 filesystem), tune2fs (adjust filesystem parameters) and e2fsck (check and repair filesystem.) ADD JOURNAL TO EXT2 […]
F is for Find
One-liners illustrating the use of the find command abound on the world wide web. The command’s operation is straight forward, but it has so many options that the man page always makes for fascinating reading. The find command is your friend whenever you need to *find* files based on name, size, file type, creation/access/modification time, […]
G is for grep
Like using the word “grok” in conversation, saying “grep” out loud brands you a SuperGeek, at least in the mundane reckoning of members of the “normal” population. They don’t understand that grep is simply an odd concatenation of the phrase “grab regular expression”; and even if they did know, it would mean nothing to them. […]
H is for Head, Tail, or Split the Difference
Head, tail and split are three of the most commonly used utilities on GNU/Linux systems for the manipulation of text files. They are tiny, sharp, and all possess some handy options of which even the experienced user may be unaware. Head returns the first lines of a file or standard input. By default, it outputs […]
Using MSInfo
Do check out msinfo32.exe. Virtually everything that you would want to know about the system configuration of a Windows machine will be revealed with this command. Msinfo32.exe is located under /Program Files/Common Files/Microsoft Shared/MSInfo (at least on our system). If you wish to dump the report to a file, use: msinfo32 /report reportname.txt It takes […]
Automated Log Monitoring with LogSentry and a Central Syslog Server
Part One: Installing and Configuring LogSentry by Urbana Der Ga’had If you haven’t automated the monitoring of your system logs, you’re flying blind. By proactively identifying hardware failures, unusual patterns of user behavior, and intrusion attempts, you can often solve problems before they become painful. festering. scars that won’t heal. Oh yes! In Part One […]
Automated Log Monitoring with LogSentry and a Central Syslog Server II
Part Two: Configuring a Central Syslog Server By Urbana Der Ga’had In Part 1 of this article we installed and configured LogSentry to automate the monitoring of the system logs on our machine. That’s great if we’ve only got one or two systems, but what if we have a dozen *nix systems, or fifty, or […]
Monitoring Servers With GKrellM
GKrellM is a GPL’d multi-platform monitoring program. For a Windows port, see Bill’s Software. In this article we will get GKrellM running on 5 different systems and use client/server mode to connect via SSH, and monitor the systems from a centralized console. We are quite excited about this project because it is client/server (now), has […]
Grabbing Top Stats Remotely
One particularly useful tool for systems administration is top. One thing you may not be aware of, is that you can output the information top provides to a file. You may also not know that you can run commands like this remotely via ssh. Here is a short script that demonstrates this: #!/bin/sh /usr/bin/ssh user@domain.com […]
Using Composite To Create Status Wallpaper
We have written several articles on pulling stats from various locations and integrating them. Well, Agatha has been busy, and finally got her desktop integrated. Here is a snapshot of Agatha’s desktop using these techniques: Click for a larger image The trick to creating this desktop is to use gozer to create images from the […]
Creating Log Archives on Windows 2000
We have a process that creates a log file, and we want to archive the log files every day. The easiest way to rotate these logs is to create a batch file that copies the log file to a filename that includes the date of the file as the file name. Now, we can’t really […]
Monitoring a Bunch of Servers in Windows Performance Monitor
We recently had to monitor a farm of Windows servers with Performance Monitor. True, we could add one counter at a time from the various servers… point, click, wait, pulldown, click, ok, click…. aaarghhh. Burning hot pokers in the brain working on these boxes. Now, it turns out that you can edit the log settings […]
Ping Monitoring Over a WAN – Introduction
One problem with monitoring servers over a WAN is that the WAN is often down during the night. Now, if the WAN is down hard, that is a separate issue. But, just because a host does not respond to a ping does not mean the WAN is really down, or that the server is down. […]
Ping Monitoring Over a WAN – Main Routine
We introduced a ping monitoring program in this article. In this article, we will start documenting our script by going over the main routine: use Time::Local; use Mail::Sendmail; use Net::Ping::External qw(ping); $pmwrap=0; while (6 ne 9){ # Loop forever… I don’t mind. system(“cp new.dnsf dnsfc”); # Each pass through the servers, copy dnsf again to […]
