This week's survey is inspired by this morning's Kimberly+Paul hot-tub conversation around data-dependent routing vs. network load balancing, which then turned to SLAs. Yes, we lead an exciting life .

This survey is a *four*-parter. Part 1 is for each of your databases, which survey option is closest to your target maximum allowable downtime SLA (Service-Level Agreement, a.k.a. RTO – Recovery Time Objective)?

  • Survey 1 is if your SLA is based on 24×7 operation
  • Survey 2 is if your SLA is based on non-24×7 operation (e.g. allowing for a 6 hour daily maintenance window, the rest of the time we must be available 99.9%)

Part 2 is for each of your databases, what can you actually achieve?

  • Survey 3 is your achievement over the last year for 24×7 operation
  • Survey 4 is your achievement over the last year for non-24×7 operation

I'll report on the result sometime during the first week of June – as this is a big survey I'd like to get lots of results. Please repost/Tweet/whatever.

What do I mean by that downtime SLA? Well, however you have it defined. It could be that your SLA is an absolute value based on 24×7 operation, or it could be based on the 9-5 work-day. In all cases, what percentage of the defined time does the system have to be available? Note that I'm calling out a 5, 4, and 3 nines of 24×7 as separate answers as I'd like to see how often these occur and can be met.

As always, a big Thanks! for contributing to the blog by responding. Please shoot me an email (Contact button, bottom left of the blog), or ping me on Twitter (@PaulRandal) if you have an idea for a good survey.

PS No comments on this post please (I'll delete them straight away) – please wait for the survey results post to avoid skewing the answers.