26 Nov 07 FreeNAS as Disaster Recovery
Disaster Recovery - is the process of regaining access to the data, hardware and software necessary to resume critical business operations after a natural or human-induced disaster.
Most small to medium size companies do not have a DRP (Disaster Recovery Plan). Most believe that a nightly back-up with the storing of the back-up tape off-site is sufficient enough to over come most disasters. Maybe for some, but what happens when all your equipment is destroyed (Fire, water damage, etc)?
I will walk you through a procedure that we have just implemented that uses FreeNAS and some open source utilities to create a disaster recovery site with access to all current-up-to-date data from your network.
FreeNAS - is a free NAS (Network-attached storage) server, supporting: CIFS (Samba), FTP, NFS, resync, protocols, local user authentication, and software RAID (0,1,5), with a web-based configuration interface.
FreeNAS Setup:
Setting up FreeNAS is very basic and quick. You can download the latest ISO image here.
Any PC/Server will do, although be sure you have sufficient Hard Disk capacity that can backup your entire data structure. I would recommend the use of 2 identical HDD when setting up the NAS server. This will give you the ability to provide fault-tolerance with RAID or other redundant options.
Install the NAS operating system (only about 32MB) on a USB memory stick or if you have a small hard disk drive that would work as well. Do not install the operating system on any of the disks that you will use to back-up the data. This will allow you to utilize the complete hard disk drive space.
Once NAS has been setup and configured for your domain (IP address, hostname, AD settings, etc), we are ready to begin with our DRP setup.
HDD Configuration:
Format the HDD using the UFS (Unix File System) file format. Ideally, both HDD should be the same size. Once you have formatted the HDD, create a mount point on the first available disk. In our scenario, we have created a mount-point called ‘online_backup’.
On the second HDD we created a mount-point called ‘backup’.
FreeNAS has a built-in utility called resync. Resync is a multi-platform incremental copy over the network utility that can be used for backup. The incremental sync process permits a copy of the differences in the files across the link, from the last backup.
Configure the NAS server as the resync server. Once the resync server has been configured, you will need to download a resync client on your file server. We use Windows 2000, so we installed one of the many ported resync client tools for Windows.
Once the resync client has been installed on the server, you can customize which folders/drives you want to sync with resync server. Once all the folders/drives have been selected, you can schedule the resync to perform at each hour or nightly (choose a time after your original backup for the first resync).
Once you have the folders/drives in place to be copied and the schedule according to your needs, you are ready for the initial copy of all the data to the NAS box. Once all the data has been synced to the resync server, within your NAS box, configure the resync client (your backup mount on disk 2) to sync data from the online_backup mount on disk 1. This will give you a mirror of your data on 2 drives.
We then placed the NAS box to our remote office to sync daily with our file server. So in case of a disaster at our HQ location, clients can be redirected to our remote site to access the files that have been sync’d with our data server from the last schedule.
To ease the transition when testing, we have created a script that will automatically deploy network shortcuts on the desktop for all users to access the recovery server during testing/disaster.
Please check out the following sites for more information on FreeNas and Disaster Recovery.
