SQL Server Administration skills jump start (13/100)
By Shehap El-Nagar
By the last blog , I explained some DMV stacks related to backup and now I will try to fancy bit more my scope of writing to include NOT ONLY DMV stacks but cmd and power shell (cmdlet) prompts that are commonly used for various DB administration tasks ,in this blog I will explain one of the most trickier scenario that if happened it means catastrophic case and indeed most of DBA will think about the destructive action which is destroying the current DB cluster /server and rebuilding a new DB cluster /standalone server , this scenario is actually master and msdb DBs corruption which can end up eventually with a complete standstill case for your production DBa and thus the other interrelated systems and applications ..Terrible ..!
First a quick question here ..? Why corruption happens ..? why master DBs might reach to this catastrophic case and drill down to this culprit point ..? what indicators that can lead DBA to drive early decisions and actions to secure his environment from such awkward situations ..?
Indeed, 95% of corruption are coming out of HW reasons either related to servers or storage and less likely to be related to SQL Server , I am giving below some examples of some HW failure reasons that cause such data corruption:
Unplanned electricity outage.
Unplanned network outage.
Unplanned SAN shutdown or movement.
Unplanned Servers shutdown
Uuplanned VM machine shutdown due to network disconnect or VM host machine power failure