Playing with RAC Voting Disks

Lately I ran into a case of losing of a voting disk, so this lead me to create a GI environment on my laptop (using virtual box) and play with voting disks failures. In this post I’ll explain what I did and what happened.

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Analyzing the Listener.log

A little bit more than a month ago I spoke at OSWOUG event (and wrote this post about it). In the event, Jared Still talked about free tools for Oracle database. He basically said that there is a lot of stuff out there on the internet, and if you can’t find what you need, then write it and publish. So I couldn’t find what I need, and I wrote it, and now I publish (thanks Jared).

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Diagnosing Listener Issues in RAC

I’ve written a few “diagnostics” posts in the past (you can see them all under the “Troubleshooting” category). People really like these type of posts, and I got many comments about them in the past (good ones…), so here is another case that I had not too long ago.

I’d like to thank Kadhir Velavan, he is the guy who brought this to my attention and we worked on this issue together.

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Reading AWR Report – Part 1

Once in a while I get requests for some information about reading and analyzing an AWR report. I have been thinking for a long time about writing such a post, but always postponed it as it is a very tricky topic. The AWR (or statspack for that matter) report is huge and contains so much information that it’s easy to get lost. It also requires a lot of knowledge about the database and the different mechanisms so it’s very difficult to explain all of this in a blog post (or even a series of posts). In this post I’ll try to start from the beginning, explaining a little bit about the AWR report and the analysis process and we’ll see where it takes us.

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Scanning an Index

The internet is full of information about indexes, and for a reason. Indexes in a database is probably the most important performance related topic. There are so many cases, properties, and different ways to use indexes that there is simply a lot to write about. In this post I’d like to talk about a specific use case that I’ve seen a few times, and is related to index scans and performance.

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