Sunday, November 13, 2005
King Of All Backups! (AKA LAN-Free to Disk)
About a year ago we were tasked to setup a large multi-clustered Exchange server and provide the best possible backup and restore performance. After much debate and research we decided on using LAN-Free to disk. The system was a 7 node Windows 2003 cluster connected to an SAN disk array (I can’t remember if it was EMC or Dell). The first 5 nodes were Exchange servers, the 6th was the failover node and the 7th was turned into a TSM server. The TSM server instance had 5 500GB secondary disks assigned to it for the backup of the five Exchange servers. These five disks would be mapped one to each Exchange server allowing for the backup to occur across the SAN to the disks owned by the TSM server. To utilize the LAN-Free to disk capability we had to install Tivoli’s SANergy product. SANergy is no longer a separate product but is now part of a TDP/Agent type install package for TSM. We actually installed and configured SANergy first, which was easier than it seemed in the directions, then mapped the drives. When configured with SANergy the mapped drives become accessible across the SAN as long as the clients are on the same disk SAN fabric. So we now had mapped SAN-accessible drives and could backup the Exchange servers to disk using the FILE device class. The FILE device class is the device class used since TSM does not support LAN-Free backups to diskpools at this time. The FILE device class works like a virtual tape and it was configured to migrate the data a few hours before the next backup would occur, or when the storage pool reached a specific usage threshold. The reason for this was to allow almost a 24 hr. timeframe for a restore and along with the new Exchange 2003 restore capabilities internally; it provided a high performance backup/restore solution. We tested the backups against a 360GB DB and backed it up in 90 minutes. People were impressed, but they wanted to see how it performed on restore. We then restored the same amount, 360GB, in 91 minutes. WOW! It was amazing to see those numbers (68MB/s). We even tested it with the failover node by mapping all 5 SANergy defined drives to the failover node and still saw the same numbers. We had everything ready to go when the account decided they wanted to go in another direction. Weeks spent configuring and implementing the solution all for not! At least I have the experience and know it works. So if anyone is looking to do LAN-Free to disk it works, it’s fast, it takes a lot of admin work, and it will be a good solution for anyone looking for a high performance backup/restore environment.