Some of my clients, instead of engaging me for day-to-day support, engage me for expert assistance only when it all really hits the fan. This issue occurred for one of those clients, who had other support performing the HADR failovers while the Linux kernel was upgraded. The version of RedHat did not change, but the kernel did.
This blog entry is designed to serve as a roadmap for current blog entries directed at those newer to Db2. In my mind, this likely includes anyone who has been working with Db2 for less than 2 years. However, often there are areas we spend more time in than others, so I think of these topics also as “spackle” – to fill in gaps for the self-taught. Note that some of the topics below are not links. This is because they’re areas I plan to blog about in the future.
What is Db2? This article is one of my few that is not directed at a Db2 DBA or someone trying to fill some of the roles of a Db2 DBA. This is directed, as much as I can manage, at any technologist trying to understand what Db2 is and the role it plays in an IT organization.
This is the third time I have written this post. It keeps changing, so I keep sharing.
Edit: 01/23/2018 – corrected one word not in an SQL statement.
Why Should a Database be Highly Available?
It is significantly easier to implement high availability at other levels than it is at the database level. Often the database server is one of the more powerful servers in an environment, and without some fancy footwork there can be only one live copy of data. Ignoring high availability at the database level due to expense can be a bankruptcy-inducing choice for an organization. Just imagine what would happen if your databases suddenly did not exist. Not only would your company be unable to perform daily business, but the data lost could actually drive a company out of business.
Edited 12/13/2017 to correct image and details about the database heap.
Recently I was forced outside my comfort zone and asked to vet various open source BI tools. I was a report developer in a past life, a database administrator supporting datamarts at various employers, and even supported Cognos backend databases. I thought my past experience gave me an edge when it came to evaluating BI tools.