Disaster recovery backup system

August 2009

Overview

Crosfields School had an immediate need to improve their backup system, as the existing system was not automated, and was slow to perform both backups and recovery. An automatic disk-to-disk backup system using Microsoft Data Protection Manager with iSCSI storage was implemented, with end-user recovery made available so that users could restore their own file backups at will.

Need

The existing backup system used server-local DDS-3 and DDS-4 tape drives with NTBackup. The storage requirements had outstripped the capacity of the tapes and backups regularly exceeded the overnight slot allocated to them. As a result, some historical user data had been shifted from the main storage servers and onto DVD archive storage, which caused inconvenience to users who had to request access to this data in advance when needed. The available tapes allowed for daily backups to be kept for only 6 days, and weekly backups to be kept for 4 weeks.

Considerations

• Automating the backup process was highly desirable to free up staff time.
• Increasing the backup storage capacity to encompass all user data was required, as well as to increase the number of daily backups that could be retained.
• Backup storage needed to be kept distant from the main servers so that backups would be safe in case of a physical disaster (e.g. fire, theft, lightning strike).
• The introduction of bare-metal backups was highly desirable, so that an entire server could be restored in the event of loss, instead of having to reinstall the server and restore the user data.

Solution

• Microsoft System Center Data Protection Manager 2007 was deployed onto a Hyper-V guest.
• Backup storage was provided by a Netgear ReadyNAS 2100 with 3GB of RAID storage, connected to the backup server using iSCSI over a 1Gb fibre connection. This allowed the storage NAS to be located in a communication cabinet on the opposite side of the school site, 120m from the main server room.
• Power backup was provided by an APC Back-UPS 800, providing 40 minutes of battery backup power to the storage NAS.
• A separate LUN was provisioned on the NAS to allow the DPM backup server itself to be backed up using Windows Server Backup, so that loss of the backup server would not require a time-consuming re-installation.
• Storage was sufficient to allow additional LUNs to be provisioned for backups of non-critical servers with simple backup requirements (such as print servers) using Windows Server Backup to reduce licensing costs for DPM.
• A separate VLAN was implemented to separate iSCSI traffic from the main network.
• Daily backups configured to be kept for 30 days

About Crosfields School

Crosfields School is an independent day prep school in Reading, UK. It currently has around 510 pupils aged 3-13. James Schlackman has been the Network Manager at the school since June 2009, supporting a network of around 140 workstations and 16 servers, based on Windows 7 and Server 2008 R2.