At one time, I felt that NAS had a rather distinct disadvantage. While it did significantly reduce system administration requirements, it created a challenge in one particular area - backup and recovery. Since most NAS filters usually involve a stripped-down version of the operating system, normal backup and recovery client software often isn't applicable. With a few exceptions, you can't simply buy client software from backup vendor for your filer. Although this has gotten better, there was a time when the only way to back up your NAS appliance was to use rump or to back it up via an NFS mount.
Even the advent of the network data management protocol, didn't seem to help things at first. It usually meant locally attaching a tape drive to a filer and backing up that server's data to that tape drive. This often meant a significant reduction in automation. It didn't help that software vendors were slow to support NDMP, because they saw it as competition to their own client software.
However, a lot has changed in recent years. All major backup-software vendor support NDMP, and you can even use SAN technology to share a tape library between your filers and your other backup servers. Even if you're backing up your filers across the network, gigabit NICs that offload the TCP/IP processing from the host CPU make data transfer over the network much easier and faster, Jumbo frames also helped some vendors.
Another reason that backup and recovery of filers is now less a problem is that some NSA vendors introduced data-protection options equivalent to the options available on many Unix or NT system - including built-in snapshots, mirroring, and replication. Therefore, for what it's worth, my respect for NAS has grown signigicantly in recent years.
Wednesday, January 20, 2010
Friday, January 15, 2010
Subscribe to:
Posts (Atom)