Diagnosing a SAN problem requires a fair amount of information, because three different kinds of equipment are involved (hosts, storage devices and -- usually -- switches). When you present your problem to vendor tech support, it's a good idea to have all that information organized and at your fingertips.
So it pays to have a checklist of information that puts all of it on a single screen, or a single sheet of paper. In addition to the obvious -- the nature of the problem and the troubleshooting steps already performed -- here are some other things the checklist should include:
- The OS version and patch level of the host;
- The types of HBAs and their firmware and driver versions;
- The type of storage device, its firmware level and its serial number.
For the typical enterprise with one or a few SANs, the appropriate information can be pre-entered on the form. This is especially true of things like serial numbers, which may not be readily available to the person reporting the problem.
Brocade has a sample technical support checklist on its Web site.
Rick Cook has been writing about mass storage since the days when the term meant an 80K floppy disk. The computers he learned on used ferrite cores and magnetic drums. For the last twenty years he has been a freelance writer specializing in storage and other computer issues.
