Here's how to set up relatively cheap redundant iSCSI storage on Linux. The redundancy is achieved using LVM mirroring, and the storage servers consist of commodity hardware, running the OpenFiler Linux distribution, which expose their disks to the clients using iSCSI over Ethernet. The servers are completely separate entities, and …

I always forget what the correct options for the Windows xcopy command are when I simply want to synchronize one directory over another one, so that only changed files are overwritten. To do it well, you need to remember too many options. And robocopy is never installed when you need …

First, create a key-pair with ssh-keygen. This is a one-time operation.

ssh-keygen -t dsa

It is good practice to enter a good password, but you may also leave the password empty. That will leave your private key vulnerable to local attacks, but if you need to login somewhere from a …

I upgraded my Lenovo Thinkpad X300 to Ubuntu 8.10 Intrepid Ibex today. My original installation notes for Hardy are here.

After the upgrade, sound was working without compiling an ALSA snapshot by hand. Also, 3G connections worked straight out of the NetworkManager applet, which is very nice. But WiFi …

I was not able to compile PHP 5.2.6 with IBM HTTP Server 6.1 as a module, so I compiled it as a CGI binary instead. Here's how to do it.

Ths SSH protocol supports tunneling arbitrary ports from your local host to a remote network that is only reachable through a remote gateway machine. The typical situation is that you have a, say, web server in a network which is only accessible from inside the network. If you have an …

Here's how to make dynamic IPv6 routing work between a Cisco IOS router and an OpenWRT Linux Quagga router. I couldn't find a similar howto anywhere, so I decided to write my own.

I am using OpenWRT Kamikaze 7.09 (kernel 2.4) on an ASUS WL-500gP wireless router. Any …

This document describes how to set up a Sendmail e-mail gateway or relay which will be able to process incoming mail and route it to different mail servers based on domain information. The routing table is based on the Sendmail mailertable feature instead of the usual MX record based routing …

Network interfaces can be bonded to provide fault-tolerant operation. Here's how to do it in Ubuntu. I will assume the interfaces to be bonded are eth0 and eth1.

First, install the ifenslave package. The ifenslave tool will be used to actually bond the interfaces.

apt-get install ifenslave

Create file /etc …