Server and Network Monitoring with iPhone
February 25, 2010 – 6:53 pm | No Comment

What is a Unix sysadmin doing with an iPhone, you ask? It was a birthday present, if that’s all right with you. I know, I should have gotten something odd with a beta version of …

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

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Articles in Networking

Windows Network Troubleshooting Script
January 20, 2010 – 10:15 pm | One Comment
Windows Network Troubleshooting Script

I try my best to stay away from Windows. I wish my clients did the same. The usual difficulty of troubleshooting elusive network performance problems is amplified many-fold when there is a Windows computer at the end of the line. With Unix it’s relatively simple: run tests “a”, “b”, “c”, etc and follow the familiar process of elimination. With Windows in the picture the number of steps uses up all of the English alphabet and spills over well into the Russian one. And when you finally reach step “я”, you have to pull out your Chinese dictionary.

Copying Data: Are We There Yet?
December 27, 2009 – 7:12 pm | No Comment
Copying Data: Are We There Yet?

I am sure this will sound familiar: you are copying a large amount of data – either locally or over the network – and you are wondering how long it will take and if there is a way to make things go faster.You may be surprised, but it does matter what type of files you are copying: 1Gb-worth of many small files will take considerably longer to copy than two 500Mb files. The hardware you are using is an important consideration, but it’s not the only factor limiting data transfer speed.

Printing from SuSE/SLES to a Windows Printer
December 10, 2009 – 5:05 pm | No Comment
Printing from SuSE/SLES to a Windows Printer

The following document explains how to configure your SuSE or SLES system to be able to print to a remote printer shared from a Windows server. The first step is to install Unix print support …

Reboot Remote Windows Workstation
December 10, 2009 – 9:53 am | No Comment
Reboot Remote Windows Workstation

When using RDP, sometimes the session may lock up and you may need to reboot your workstation remotely. This can be done using the “shutdown.exe” command from your local PC. First, make sure you can …

Slow SSH login in SuSE Linux
November 3, 2009 – 6:17 pm | One Comment
Slow SSH login in SuSE Linux

Starting with SuSE 10 and including both openSuSE and SLES an annoying SSH problem appeared. When you SSH to the server (via PuTTY and such) you get the “login” prompts right away, but the “password” …

Automatically Validate HTTP Proxies
August 5, 2009 – 4:14 pm | No Comment
Automatically Validate HTTP Proxies

Let’s say you downloaded a long list of Web proxy servers. Now you are stuck with the task of weeding out the proxies that are dead, slow, fake, or otherwise unusable. There are some applications …

Sharing Videos from Linux to Xbox 360
December 19, 2008 – 8:49 pm | No Comment
Sharing Videos from Linux to Xbox 360

Xbox 360 uses UPnP protocol to stream multimedia files from computers on your home network. Normally, you would have a Windows PC running WMP and sharing files. But what if you have a Linux box …

Linksys WAP54G Secure Configuration
June 11, 2008 – 1:09 pm | No Comment
Linksys WAP54G Secure Configuration

Below are some basic steps to secure a wireless access point (WAP). The screenshots are for Linksys WAP54G v. 3.04, however, the same steps will apply to wireless access points from other manufacturers. Understand this: …

Migrating email between hosted providers
May 23, 2008 – 9:38 pm | No Comment
Migrating email between hosted providers

Recently I ran into a small problem. A customer of mine was moving her site to a new hosting provider. Her old provider was Windows-based and her new provider was Linux-based. The old provider did …

Protected: SuSE Mail Transfer Agent Configuration
February 7, 2008 – 3:48 am | Enter your password to view comments
Protected: SuSE Mail Transfer Agent Configuration

There is no excerpt because this is a protected post.

Configuring eMule for Best Performance
December 27, 2006 – 12:22 am | No Comment
Configuring eMule for Best Performance

"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 …

Simple network monitoring with ping
April 11, 2006 – 10:12 am | No Comment
Simple network monitoring with ping

In the Spring of 2005 Comcast experienced a major DNS outage. Since then many Comcast users have switched to DNS servers that belong to Verizon and other ISPs. Comcast started taking a lot of flak …

CUPS printing on Solaris 10
February 28, 2006 – 12:08 pm | 2 Comments
CUPS printing on Solaris 10

Download the Companion CD for Solaris 10 GA on: Solaris 10 Companion cd download

bunzip2 software_companion_sparc.iso.bz2 #unzip the file
 
lofiadm -a /export/data/software_companion_sparc.iso #mount the ISO image
mount -F hsfs -o ro /dev/lofi/1 /mnt #mount the ISO as a …

Accessing Samba server in DMZ
January 22, 2006 – 2:04 pm | No Comment
Accessing Samba server in DMZ

This note explains how to access a Samba server located on the “orange” DMZ subnet from a Windows PC on the “green” LAN. The problem for Samba is caused by the firewall blocking NETBIOS responses. …

Installing SuSE Linux 10 on a laptop
December 10, 2005 – 7:53 pm | One Comment
Installing SuSE Linux 10 on a laptop

What’s the best Linux distro for desktop applications? My subjective opinion based on years of Linux experience is that SuSE 10 at the moment offers the best combination of features and user friendliness. The latter, …

Configuring multi-IP network interfaces
December 2, 2005 – 12:18 pm | No Comment
Configuring multi-IP network interfaces

This article explains how to configure a network interface to support virtual IP addresses. This is useful in a cluster environment or in any high-availability service cnfiguration, when you need to ensure that at least …

Basic Network Configuration Under Solaris
November 26, 2005 – 1:27 pm | No Comment
Basic Network Configuration Under Solaris

The following document provides a general overview of the network configuration process for Solaris. For a detailed review of Solaris network configuration please see Chapter 4 of the O’Reilly Solaris 8 Administration Guide by Paul …

FTP script with nested function
November 20, 2005 – 2:14 am | No Comment
FTP script with nested function

An example of an FTP script with Korn shell.
For “$CONFTMP” input file of format: hostname username password

cat "$CONFTMP" | fgrep -v "#" | while read LINE
do
FTPHOST=$(echo "$LINE" | awk ‘{print $1}’)
FTPUSER=$(echo "$LINE" | awk ‘{print …

Using FTP with pipes
November 19, 2005 – 10:37 pm | No Comment
Using FTP with pipes

Pipe in Unix is a method of passing information from one command to another. The pipe take the output of the first command and sends it as input for the second command. The a second …