May 12 2015
Alerts have been around for as long as I can remember, so some time before breakfast. That probably means you need to get a wriggle on and upgrade to SQL Server 2014. If you are still wondering whether to upgrade I did write a post on it some time back which may help: 5 Top Features Your Company Can Use in SQL Server 2014 Standard Edition
This post isn’t about how to create alerts in SQL Server, which have been around for over 15 years now (if you’re not sure how to do it Let Me Bing That For You) neither is it about why you should be using alerts – I mean come on it’s pretty obvious.
What I did want to bring your attention to is a particular alert that a lot of people miss.
Queue the big font.
Error 825 is a bit of a strange one and easily missed because it’s regarded as a severity 10 informational message – which is completely bonkers!
This is what KB article 2015757 says about how the error is logged:
An Information Level message will be written into the Windows Appliction Event Log with EventID = 825. Since the operation was successful after one or more retry attempts, the client application does not see any error or this message.
Nice, so if it’s only marked as informational it can’t be that important can it? Yeah it kind of is, so is spelling but we’ll let the spelling mistake in that quote go.
Error 825 let’s you know that there has been a failure with an IO operation, but it’s OK because we retried it and everything is fine now.
Really?!?! In my opinion if you see any kind of error relating to IO you need to be all over it like Bear Grylls on an alligator.
Please do have a look at the KB article which goes into further detail on how to go about troubleshooting the error.
Most people create alerts for levels 19 and above to capture all of the “Fatal Errors”, please don’t fall into this trap. Make sure that you are safeguarded against this issue with an explicit alert for 825. I would also say you should create alerts for 823 and 824 too.
Thanks go to Cathrine Wilhelmsen (@cathrinew) for hosting this month’s T-SQL Tuesday and choosing the topic of Monitoring. Also a big thanks to the person who bet I couldn’t fit in the word “alligator” into a blog post on SQL Server.