Based on the Grid Infrastructure, RAC One Node is a RAC Database with only one instance running. This architecture reduces unplanned as well as planned downtime. If the server crashes that holds the instance of a RAC One Node database, that instance can failover to another node in the cluster automatically. If we need to take down the server (or the clusterware stack there) because of a maintenance task, we can do an Online Database Relocation:
The demo was done with 11gR2 and it is very similar to what I show live during the Oracle University course Oracle Database 11g: RAC Administration about RAC One Node. Hope you like it 🙂
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#1 von sgyurov am Oktober 14, 2013 - 16:17
Hi Uwe,
RAC One Node is a great concept and works pretty well, BUT it would be much more used if it was part of SE or even if it wasn’t an option.
By the way, I’ve delivered presentation (http://sve.to/papers/) on that two years ago and it looks very much like your video 😉
That’s the planned downtime – https://vimeo.com/76864571
I was thinking these days to give it a try with Oracle 12c and check if there are any new features and see how it works.
Regards,
Sve
#2 von Uwe Hesse am Oktober 14, 2013 - 16:29
Sve, thanks for your comment and the link to your presentation & video! That is a nice addition to see how it can be done with the Enterprise Manager. Well, I always try to stay clear from any license related discussion – fortunately, I never have to pay for the Oracle products I use 🙂