Oracle RAC with SRM 5.1

[D1Q4]

Hi, good day to all of you..

Does anyone's here ever implemented or tested Oracle RAC protected with Vmware SRM ?

Does VMware SRM 5.1 support Oracle RAC?

As i know, the RAC VMs shared they virtual disk to another RAC VMs. in my configuration the RAC-B VMs had 7 virtual disk mapped to RAC-A VMs and all works fine in production environment and they've plan to protect this RAC VMs with VMware SRM 5.1. we are using Array Based Replication with EMC RecoverPoint as the SRA.

When i try test failover my protection group which is containing those two VMs, the RAC-B VMs not able to start with the following error

The mapping virtual disk prevented the VMs from boot up, and there is no snapshot either from the RAC-A or RAC-B.

Then i edit the VM Start up action from Recovery Plan, im setting the RAC-B to not power on at recovery site. and manually map the virtual disk after test failover, and the RAC-B still can't booting up.

Please give me some enlightenment, how to map the virtual disk after failover to recovery site.

Thanks Before

Rgds

Dika

[D1Q4]

Hi Guys,

Any idea how to protecting VMs with sharing VMDK with VMware SRM 5.1?

im still struggle to fix this issue.

Thanks Before,

Rgds

Dika

[mal_michael]

Hi,

Are your VMs configured with shared bus or are you using multi-writer flag?

Michael.

[D1Q4]

Hi Michael,

Thank you for your response.

Im configured the VMs with shared bus.

Rgds

Dika

[mal_michael]

Do all of the VMDKs (including OS) reside on same datastore?

Do both VMs being powered on on the same host or different hosts?

[D1Q4]

Hi Michael,

Do all of the VMDKs (including OS) reside on same datastore?

No, They are reside on different datastore.

Do both VMs being powered on on the same host or different hosts?

The VMs running on separate host, even at protected site or recovery site.

Rgds

Dika

[mal_michael]

When you run a recovery, do all of the hosts have all of the datastores available?

Can you try to perform a recovery to a single host? I mean either enter all the hosts except one of DR cluster into maintenance mode or take one of the hosts out of the cluster and configure it as a target of these VMs thru inventory mappings.

Michael.

[D1Q4]

Michael,

Yes, all of the host on recovery site able to see all of the datastore.

i can try what you've suggest but i need to restore my VMs back to DC site.

Because My current conditions, i already run the recovery to the DR site but doesn't reprotect the VMs at the DR site yet. how can i reverse my VMs to DC site without sync the datastore from DR to DC site? because both RAC VMs working properly before. im affraid if i reprotect the VM at DR site and recovery back to DC, im not able to powering on both VMs at DC site..

Rgds

Dika

[mal_michael]

You cannot perform a test without reversing a replication.

What are exact versions of SRM and hosts (build numbers)?

Just to make sure: you don't have multi-writer flag configured in addtion to shared-bus, right?

Michael.

[D1Q4]

So sad, there is some possibilities if im reprotect the VMs at DR site and recovery/failback to DC site my VMs would not be able to power on?

im running SRM 5.1.0 and ESXi 5.1.0 build 1117900..

yes,pretty sure mal,.. the only scsi name exists at configuration parameters only scsix:x.ctkEnable with value "true". and there is some .ctk files in datastore.

is it possible if this ctk files whos prevent the VMs from powering up? because from the error stack state "could not open/create change tracking file".

But who is create this .ctk files? SRM does?

Rgds

Dika.

[mal_michael · Accepted solution]

Good find!

ctk files are being created by ESX when CBT (Changed Block Tracking) is enabled. CBT is used by backup software and is not supported with disks using shared bus.

So this definitely may cause issues.Do you have any backup solution for these VMs?

CBT may be disabled (requires VM downtime):

http://kb.vmware.com/kb/1031873

Michael.

[mal_michael]

Furthermore, one of my colleagues pointed out that your setup is not according to the RAC on VMware configuration guide:

http://www.vmware.com/files/pdf/solutions/oracle/Oracle_Databases_VMware_RAC_Deployment_Guide.pdf

The valid options are:

1. VMDK using multi-writer flag

2. Virtual mode RDMs using multi-writer flag

3. Physical mode RDMs using physical bus-sharing.

Consider reconfiguring your setup.

Michael.

[D1Q4]

Hi Michael,

Yess right, the .ctk files prevent my secondary VMs from power-on...

after changing the value from scsix:x.ctkEnabled to "false", the secondary RAC VM now able to power on..

actually im still rather confuse who is creat the .ctk files because i didnt implement any backup sollutions..

in my opinion the EMC SRA create the .ctk file, because they handle sync storage between DC to DRC and to keep data consistency the SRA using CBT. CMIIW...

one more questions mic,

if im enable the multi-writer flag, can still use SRM to protecting my VMs?

because in my understanding, refer to this document http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=10341...,

VMs with multi-writer flag enabled cannot using SRM.

Rgds

dika

[mal_michael]

Good news. I am glad both VMs are up and running.

I am not RecoverPoint expert, so cannot say if RecoverPoint has enabled CBT.

Have you deployed these VMs from template? Maybe it is enabled on the template VM.

My colleagues confirm that SRM does work with multi-writer flag (using array based replication).

Regarding the statement in the KB, it only relates to vSphere Replication that cannot be used with shared VMDKs.

I will try to get the KB fixed.

Michael.

[D1Q4]

Thanks a lot Mic, you are NiceExpert..

[nufael]

Hi Mic,

Do you have any experience dealing with backing up VM oracle RAC nodes with scsi bus (non-sharing option) and multi-writer disk enable? Since the snapshot is not supported for disk with multi-writer enable, is there any other way to backup these type of VM

Regards