Category: System Administrator

Installing Kernel-based Virtual Machine (KVM) on Debian 7

debianBefore you even install KVM on your freshly installed Debian machine, you need to make sure that your machine can even run the KVM virtualization. Most computers will have to enable virtualization through the BIOS as it is mostly disabled by default.
And you will get an error when you try and install KVM. There are even some computers that can not run it all together.

The most common way to enable virtualization is by pressing either F8 or F12 as your machine starts up, to enter the BIOS. Look for System Configuration and Enable Virtualization Software.
Keep in mind that this is different from machine to machine and could be something entirely different, and the steps might be a bit more convoluted, so you might have to do a little search on the internet to work out how to do exactly it on your computer.

When that is done save and reboot the pc, and let it load up your Debian. Go to the top left corner click on Applications -> Accessories -> Root Terminal and type the password for the Root user.
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Create Cisco Switch with IOU [IOS On Unix] Loaded on CentOS

ciscoThe tutorial describes steps required for creating Cisco switch based on IOUl2. The Qemu image with installed CentOS Linux is loaded with IOU image. The IOU (IOS on UNIX) instances are attached to the network using iou2net.pl script written by Jeremy L. Gaddis. The script forwards frames between a IOU instance and a Qemu network adapters. The script is started using tap mode when Qemu interfaces are bridged with virtual tap interfaces.

1. Create Qemu image

/usr/local/bin/qemu-img create -f qcow2 ./centos6.0-ioul2.img 2000M

2. Download CentOS 6.0 minimal install CD

wget http://centos.arcticnetwork.ca/6/isos/i386/CentOS-6.0-i386-minimal.iso

Start Qemu image with attached CentOS minimal CD. Read more

PostgreSQL Backup and Recovery with Barman

dbRecently a friend pointed me in the direction of a rather useful piece of software for doing quite funky things with backing up and restoring PostgreSQL databases.

Most organizations I have seen using PostgreSQL and MySQL have always chosen to perform database backups locally on each server. This is fine and it works, but you need to ensure you take a backup of those backup files. I’ve not come across any piece of software that will do complete database backups remotely… that is, until now. This is where “barman” fits in. You can check out what they are all about on the project’s website. http://www.pgbarman.org/

In this article I’ll be going through a really quick howto on getting up and running with Barman in order to perform remote backups of postgresql servers.

In this example I will be using the below details. Read more

Configuring Dovecot to authenticate FreeIPA users using Kerberos (with Single Sign On)

monitorI have also posted this article on the FreeIPA.org project wiki which is linked here

The below details will walk you through how to add a Red Hat Enterprise Linux 6.2 system to an IPA domain, and then configure Dovecot to allow single sign on to user mailboxes with IMAP/S.

Details of this example are as follows

   Domain name: example.com
   IPA Server: ds01.example.com
   Dovecot Server: mail01.example.com
   IPA Client: workstation01.example.com
   IPA User: user1 and user2

Please Note: This guide describes using SSL combined with Dovecot to deliver IMAPS support. This guide is not designed to cover how to create a valid SSL vertificate. This guide uses the default dovecot generated certificate and it is HIGHLY recommended that if you wish to deploy this into a production environment, that you replace this certificate with your own trusted/validated certificate Read more

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