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There are some things to be aware of with ongoing support of a HADR system. I thought I’d group them together to provide a primer of do’s and don’ts for support of HADR.
HADR does occasionally stop all by itself.… Read the rest
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In this blog post, I will share what I learned about DB2 automatic bufferpools when using HADR.
In a DB2 10.5 (fp3a) HADR environment, during heightened database activity on the primary database, there was delayed log replay on principal standby database.… Read the rest
Continue reading »I have written quite a few articles on TSA, but thus far, they’ve been strongly focused on the basic how-to. I think this is because so many of us start with the how of a technical topic. As my knowledge has advanced, I have developed more advanced presentations on TSAMP, but I need to also bring that content into the blog.… Read the rest
Continue reading »NOTE: Please do not attempt to architect a high-availability solution without a DB2 expert involved. There are many questions and answers needed beyond those here to make the best decision and ask all the tough questions.
High Availability and Disaster Recovery often have different goals and priorities.… Read the rest
Continue reading »The HADR Calculator is one of three HADR tools provided by IBM on developerWorks. For more details on the other(s), see:
HADR Tools: the HADR Simulator
For the full technical specifications and details on using the HADR tools, see:
https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/DB2HADR/
The DB2 Log Scanner is one of three HADR tools provided by IBM on developerWorks. For more details on the other(s), see:
HADR Tools: the HADR Simulator
For the full technical specifications and details on using the HADR tools, see:
https://www.ibm.com/developerworks/community/wikis/home?lang=en#!/wiki/DB2HADR/… Read the rest
It is very possible to support DB2’s HADR using TSA to automate failover without understanding many of the TSA components and details, and even the TSA commands. I’ve posted several blog entries on TSA issues resolved without any deeper knowledge of things.… Read the rest
Continue reading »I have not made extensive use of the HADR Tools that IBM offers in the past. Most of my HADR setups to date have either been same-data-center using NEARSYNC or have used ASYNC to copy data between data centers. I haven’t had much cause to tweak my network settings or change my SYNCMODE settings based on hardware/networking.… Read the rest
Continue reading »A story of fail and recover.
Sometimes, I think that I subconsciously knew that something was wrong. I woke up before 5 AM and couldn’t get back to sleep for no real reason that I could figure out.… Read the rest
Continue reading »Are you ready yet? Have you started to throttle your work for the week, arrange a backup, even packed a bag? The 2014 IDUG Technical Conference is only a week away.
Ember did a fantastic job on her IDUG write-up, so I am not going to duplicate her effort.… Read the rest
Continue reading »I monitor HADR closely, and want to be paged out if HADR goes down. Why? Because any subsequent failure would then be a serious problem. Once HADR has a problem, I suddenly have a single point of failure. That said, for some clients we have to tell our monitoring tools not to alert on HADR during online reorgs.… Read the rest
Continue reading »One of the features I would most like IBM to add into DB2 is the managing of TSA States through DB2 commands. I’m not a TSA expert, but I would like to find a class or opportunity to study it further.… Read the rest
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