Capistrano for the sysadmin

There's always been a fine line between a good sysadmin and a programmer. Capistrano is software built for Ruby on Rails to make deploys across multiple servers easy, however, the potential is much greater than just code deployment. I have recently grown in love with how easily I can run commands across groups of servers, and setting up Capistrano is not a difficult task. If you've ever configured password-less SSH access, you can get this up and running without much difficulty.


Central login management with OpenLDAP

Over the weekend I spent some time learning how to configure OpenLDAP to provide a central login server at home. This is pretty useful since I was tired of either syncing UID/GID's across servers or setting directories to 777 on my NFSv4 server. I chose Fedora 12 as my OS for the server, and will show how easy it is to configure authentication on both Fedora and OpenSolaris.


Perl: wrapper for virt-install to provide iSCSI storage pool creation

So I've been working on a setup for virtualization, where currently I'm using one large iSCSI target from an OpenSolaris machine. It occurred to me that there is a downside to this. I cannot use zfs snapshots for individual machines and backups/restores will be more difficult. I also did not want to be hassled with having to connect the iscsi targets using iscsiadm every time I spin up a new VM.


Kernel Virtual Machines using libvirt

I use iSCSI from a giant ZFS storage pool in order to setup virtual machines. There's a couple advantages to this, as you get the power of ZFS snapshots and the ability to grow your virtual machine's disks fairly easily. To make administrating things a bit easier, I use one large iSCSI target and put LVM on top of this. So really this article will apply to anyone that wants to use logical volumes for their disks, which is much preferred over using files.


Ultimate File Server: OpenSolaris and ZFS

When picking out a solution for your central file server, there is of course many options. None of them quite stack up to the ease of administration and redundancy, out of the box, as OpenSolaris and ZFS provide. With ZFS you can build cheap storage arrays with disks of varying size and different levels of redundancy. For this setup I'm going to go with a basic raidz configuration using 4x 1TB SATA drives.


Announcing FreePanel

What's been keeping me busy? Well I've been working for a managed hosting company (DataPipe) and that has been the biggest source of time suck for me. Outside of that I've been working on some Perl modules to make administrating load balanced servers as easy as possible. For now, read the source if you want to know more:



Playing with libnet

I wrote a function that writes packets to the wire. It takes the source IP, destination IP, and destination port. The fucntion, writePackets(), uses the libnet headers. On ArchLinux these can be installed with pacman -Sy libnet. I was inspired to write this because I am in the process of reading Hacking: The art of exploitation by Jon Erickson. It covers a lot of the basics of reading assembly as well as some often over looked programing flaws that lead to buffer overflows.



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