How to restore a missing blob from replica cluster

Hi Helmut.

Thank you for you answer. Where can I download the Restore ClipList Utilities 1.0.1 ?

Best regards

Dejan

Hi Dejan,

Please consult the Centera Online Help:

Perform a C-Clip List Restore with a CA

Before you can perform the actual C-Clip list-based restore using the CLI, you must first prepare a C-Clip list and obtain a Content Address (CA) for the C-Clip list.

This procedure assumes that you already have installed the EMC Centera Restore ClipList Utilities 1.0.1.

Prepare for a C-Clip list Restore with a CA

1. Construct a C-Clip list file that you can restore with based on the requirements of the C-Clip list format.

Best Regards

Helmut

A CD with the Centera tools is part of the delivery of the Centera.

Install these and you will it on “C:\Program Files (x86)\EMC\Centera\4_x\SystemOperator\RestoreUtilities”

Best Regards

Helmut

When I try to issue the bellow command

getClipList.bat -a "10.241.62.38" -p d:\xyz.pea -c clipId -f dataFile.dat

I need to provide the the clipid. I don't know the the address of the clip, I only have the blob-id,

For example: I know the missing blob id 3OPAFKC39NQ36xE41V0N15238UVG418CP66A3J0O59F46BI799VR1. But for the restore I need to get a clip-id. If I try to use the blob-id i receive an error.

How can I get a clip-id from the blob-id?

I have lost only one fragment (1 blob of 6 blobs). If I get the clip-id I would then do the restore for all fragments. Right?

Best regards

Dejan

If I understand correctly. I must query a range of ClipIDs and check in the CFD for the missing blob?

Best regards

Dejan

Restore only works on ClipID (= Content Address of CDF), You cannot use Restore to migrate a single blob!

If you restore the ClipID (has an “e” in position 14) from the replica cluster then all referenced blobs (have an “x” in position 14, as in your example) will be also restored.

There is no command to get all clipIDs, which reference to a given blob (Would be nice)

Best Regards

Helmut

Please let me know how and where you identified that 3OPAFKC39NQ36xE41V0N15238UVG418CP66A3J0O59F46BI799VR1 is missing!

Just for clarification: The ClipID is the Content Address of the CDF, which is a XML style text file, stored and protected on Centera and containing pointers (=Content Addresses) to all Blobs inserted by the application during the archive process.

Best Regards

Helmut

I suggest to open a Service request to EMC or service enabled partner

Best Regards

Helmut

The box is EOS. We can't open a Service request to EMC.

I see this missing blob in a stuck regeneration report.

In this case the restore from replica cluster is the only chance to recover this error, but you need to know the cClip address.

I think it does not make sense to restore ALL objects, although the one with the missing blobs must then be recovered. (it is a big overhead for the source Centera)

What you could do is to failover the applications to replica Centera if possible on LAN and then do the “rebuild” of primary with a full restore.

Another recommended option is to get EMC support for this topic on time and material base. Ask for an offer.

Best Regards

Helmut

What method would you recomend for our case to get the correct cClip address? We would like to restore only one cClip and not the whole range.

If you find the clip ID (= Content Address) of Metadata file a.k.a. Content Description file (CDF) the simply use the restore CA method

Best Regards

Helmut

Hi Dejan,

If application can retrieve now the complete cClip, then at least the data are available again.

For any other settings/adjustments, we need the procedure provided within a maintenance contract to open a Service request.

Best Regards

Helmut

I found the missing clip ID, did a restore with CA method. I can see the missing fragments now on the nodes, but the regeneration procedure does not see the missing fragments. This is strange. To me this looks like a bug.

Is there any procedure how to "tell" the regeneration procedure where to find the missing fragments?