Keeping Your Backup Software Up To Date – Part 1
Most organizations today acknowledge the necessity of backing up their business data, however not all recognize the value of a well-oiled and maintained backup environment. Like many facets of IT, a reliable backup and recovery operation can relieve management stress and enable staff to be more productive. A perhaps over-used refrain (with a small dose of poetic license), this is not your father’s backups, when somebody changed tapes daily or weekly and offsite storage was the trunk of a car.
There are many vendors trying to win your backup business. Towards that end, new features are added and/or improved on a regular basis. This is partly to keep up with a changing application landscape, but also to make the backup and recovery operation be more reliable, more efficient, more automated, and easier to integrate and manage. The vendors may leap-frog each other, but in the long run the popular features often get assimilated by the competition. That’s good news for the backup admin, however the onus is on that backup admin to update his or her backup environment on a regular basis. Fortunately, the vendors are also making upgrades easier to manage and easier to implement. A case in point is Veritas NetBackup. In part 1 of this two part series we will discuss release compatibility.
NetBackup is currently at major release 7, often referred to as 7.x. A full NetBackup version can include multiple dot-revs, for example 126.96.36.199. The numbers have a very defined structure which plays into the upgrade and compatibility issues. The breakdown of release levels is as follows:
Some Veritas documentation also refers to the different levels as single-dot, double-dot and triple-dot, referring of course to how many dots “.” precede the number in question. Since all parts of a NetBackup version are numeric, and later versions of any section will be higher than its predecessor, just take the dots out and the higher number is always a higher version. (If no number is specified just plug in a 0.) So for example 7.6.1 is a higher rev than 188.8.131.52 (7610 > 7504).
With that in mind, a cardinal rule for NetBackup upgrades, which most NetBackup admins are familiar with: the master server version must be equal to or greater than the version of any other data-moving component in the environment. From the 7.7 Software Compatibility List (SCL):
“NetBackup does not support any scenario where a media server or client runs a minor release version or software release update version that is higher than that of their Master server.”
For example, you can’t upgrade a media server or client to 7.7.2 if the master is at 7.7.1. The reason for specifying “data-moving” is because OpsCenter can be at a higher version than the master, however it does not move any data.
Another fairly common question is backwards compatibility, and Veritas is pretty explicit here. From the 7.7 Software Compatibility List (SCL):
“For compatibility between major versions, the latest available release of NetBackup is compatible with media servers and clients that run a release of NetBackup that is up to one major version behind. However, this compatibility ceases to be supported in any configuration once the previous major version has reached its End of Support Life.”
In layman’s terms, a 7.x master server is compatible with media servers and clients running 6.x, until the 6.x is EOL. There is a similar cardinal rule here also, i.e., a client must be at the same or lower version than its media server (not counting the maintenance release). So a 7.7.2 master can have a 6.5 media server, but only clients at or below 6.5 can talk to that media server.
In part 2 of this blog series we will discuss the actual process of the NetBackup upgrade and the tools that are available to insure your success.