Shrink ASM Diskgroup and Exadata Grid Disks

Here I will cover the shrink of ASM diskgroup in Exadata environment running VM’s. The process here is the opposite of what I wrote in the previous post, but have a tricky part that demands attention to avoid errors. The same points that you checked for extending are valid now: number the cells, disks per cell, ASM mirroring, and the VM that you want to change continue to be important, but we have more now. Besides that, the post shows how to verify (and “fix”) if you have something in the ASM internal extent map that can block the shrink.


Increase size for Exadata Grid Disks

A quick article about a maintenance task for Oracle Exadata when you are using OVM and you divided your storage cell disks for every VM. Here I will show you how to extend your Grid Disks to add more space in your ASM diskgroup.

The first thing is being aware of your environment, before everything you need to know the points below because, they are important to calculate the new space, and to avoid do something wrong:

  • Number of cells in your appliance.
  • Number of disks for each cell.
  • Mirroring for your ASM.
  • The VM that you want to add the space.

The “normal” Exadata storage cell has 12 disks, the Extreme Flash version uses 8 disks per storage. If you have doubt about how many disks you have per storage cell, you can connect in each one and check the number of celldisks you have. And before continuing, be aware of Exadata disk division:

To do this change we execute three major steps: ASM, Exadata Storage, and ASM again.


ZDLRA, since 2014

In Oracle Open World 2014 the Zero Data Loss Recovery Appliance (ZDLRA) was released and it changed MAA in many ways, but two principals: protection and backup. I watched the ZDLRA presentation and saw that matched with the needs that I had that time.

After OOW in 2014 I started the project (all phases, from conception, requirements until deployments and usage) that become (in 2015) the first ZDLRA installation in Brazil, and one of the first of the world too that use replicated ZDLRA to protect both sites (primary and standby) and many levels of databases (PRO, TST, DEV). The Oracle MAA at its finest was amazing: ZDLRA + Exadata + DG; everything integrated to protect both sites.

Because of the high design level of the project it was chosen to be one of the main presentation in Oracle Open World 2015 about ZDLRA, you can find the link of the presentation that I made together with ZDLRA dev team here. As told before, in this project was integrated two ZDLRA, two Exadata and DG to reach ZERO Recover Point Objective (RPO) and Recovery Time Objective (RTO) and beside that, reduce backup time. You can see the presentation to check the scope and other details.


Exadata X8, Second look

Every year Oracle arrives and release new version of Exadata with a plenty of new things. We have the natural evolution from hardware (more memory, more cpu…) and sometimes news features from software side. The point for this post today it is not about the HW and SW things, but something is hidden in the small lines of the new X8.