VDDK - backup issue with virtual mode RDM

[Saturnous]

I am using CA Arcserve 15 SP1 with vddk 1.2.1 on a W2k3 R2 SP2 connected to a Fibrecat SAN mapped the VMFS and the RDM LUNs.

I used the vcbsandbg.exe from VCB 1.5U2 (just copied the exe + dll files - there is no VCB installed on the vddk proxy) to check if all the LUNs are visible and they are (at least comparing all the NAA.xxxxxxx ).

Whenever i backup the VM with 2 1TB RDM drives connected the job cant access the RDM drives. The drives the VM holds on VMFS are backuped succesfully and properly over SAN.

AW0551 Unable to map the VM volume to a VM disk image file. (VM Volume=[E:\])

Crawling through the vcbpopulate log gives me no hint how arcserve is aware about the drive letters withhin the VM and how it would identify them. Anyway i would espect that it parses the vmx file - found vmdks - check to access them - if VMDKs on VMFS mounting the datastore - if RDM using the same api as vmkfstools -q disk.vmdk cut out the naa.xxxxxxxxxxxxxxxxx numbers from the vml.yyyyyyyyxxxxxxxxx output - check on the proxy for this number and mount the drive. I am aware that some replication mechanism use the same NAA number for the destination LUN - which should be no issue as i espect that the vddk proxy only read from it.

I runned vddk in debug mode but could not understand the logs - they mention a lot of hexcodes - vpd pages.

I tried along with vmware-mount.exe to divide and conquer my problem - but i dont find the way to force the transportmode it uses. I succesful mounted a snapshot of the RDM but only over NBD.

1. How to force using SAN as transport mode when using vmware-mount.exe ?

2. What information are stored where about the RDMs and VMDKs - does the vmware tools publish any information about drive letters out ?

3. How the information about a VM is captured by vddk - is there a vddk command plobbing out the informations about the drives of a VM ?

4. Do i need R/W access when using vddk to backup - i tried with RO acces and it worked perfect on any vmdk on a datastore - i switched back for troubleshooting purposes.

[aruntejaswi]

vRDM is not supported with CA ARCserve Backup r15. Support is coming with version r16 that is due to release in the next few months. Remember that this is applicable only for vRDM, pRDM is not included in the Snapshot backup on the Hypervisor level by VMware and hence pRDM approach cannot be supported by backup products such as ARCserve. Here a link for more info on pRDM vs. vRDM: http://pubs.vmware.com/vsp40_e/wwhelp/wwhimpl/js/html/wwhelp.htm#href=server_config/c_comparing_raw_...

In the interim, there might be some alternatives depending upon your configuration. We usually see that customers have RDM for their Data Volumes while the C: or system volume is still VMFS.

You will be able to use VDDK to backup the C: drive or system drive on the machine using VDDK (excluding the vRDM Volumes) using RAW Mode Backup. Remember to uncheck the 'Allow File Level Restore' otherwise you would get errors in ARCserve about the other volumes. For the RDM volumes, the Client Agent backup job can be run. So you will need 2 jobs: one for RAW Mode Backup and another that uses Client Agent for RDM Volumes.

Let us know for any clarifications.

Thanks,

Arun Tejaswi

CA ARCserve(ARCserveSocial@ca.com)

[Saturnous]

That was the piece of information is the key :smileyshocked: .. would be helpful to document this somewhere "more visible" (a applicable article in the CA KB) .. and tell this the CA trainers to mention in their trainings.

This document should contain it ..

https://support.ca.com/cadocs/0/c013161e.pdf

Sorry CA when i compare your documentation with the Commvault one you definitivly loose - the GUI is too general, i can choose VDDK/VCB but i cant choose the transport mode - have to deal with registry to enable a debugging or a vddk/vcb priority - the backup job does not let me define what drives i want to backup and what not. I would suspect a more clear errormessage in case i try to do something unsupportet. I cant choose the VSS provider granulary (like with netbackup) i cant mix hardware snapshot technology with sw one in a job. I have no documentation how it works in the background (a clear checkup list for troubleshooting).

Can you post a link where CA published this info ? I was crawling days through the documentation and forums.

[aruntejaswi]

Please be aware that your feedback has been communicated to all the concerned people.

As for the KB article, we are sorry you had a hard time finding it on support.ca.com, it is listed at this link(see TEC529111😞 https://support.ca.com/irj/portal/anonymous/phpdocs?filePath=0/4536/4536_imp_techdocindex.html&fromK...

Thanks.