ECS / ViPR CAS Access Method


As of version 2.1, ViPR Services includes support of the EMC CAS API.

 

The ViPR CAS API included in ViPR 2.1 is fully compatible with the Centera SDK with the exception of the following methods

 

  • Query methods
  • Event Based Retention Methods
  • Litigation Hold methods
  • The FPPool_GetPoolInfo method will no longer return any Replica Cluster IP addresses
  • ViPR 2.1.0.2HF2 is required to migrate existing Centera C-Clips with a naming scheme which uses a 27 character length

 

Any application that currently uses the CAS API to integrate to the EMC Centera archive platform can now seamlessly access ViPR clusters.

 

General

 

1. What is the minimum revision of the Centera CAS SDK that can be used with ViPR CAS?

 

The minimum revision that is  supported with ViPR CAS is v 3.1.544

 

2. What will happen if an application that uses an older revision of the Centera SDK tries to connect to ViPR CAS?

 

The connection will fail. Note that v 3.1.544 is the oldest revision of the Centera CAS SDK that is supported by EMC and customer should upgrade if they are using it with Centera as a matter of course.

 

3. How easy is it for an application to move to a revision that is supported.

 

It is as easy as replacing the Centera CAS SDK with a later one.  Customers should discuss this upgrade with their Application provider before attempting this.

4. What Query methods are not supported by ViPR CAS 2.1

 

The following method calls will result in a error that "Query is not supported for this pool connection":

 

FPQueryExpression_Close, FPQueryExpression_Create, FPQueryExpression_DeselectField, FPQueryExpression_GetEndTime,
FPQueryExpression_GetStartTime, FPQueryExpression_GetType, FPQueryExpression_IsFieldSelected,  FPQueryExpression_SelectField,
FPQueryExpression_SetEndTime,  FPQueryExpression_SetStartTime, FPQueryExpression_SetType, FPPoolQuery_Close, FPPoolQuery_FetchResult

 

5a. Does ViPR CAS support Retention Periods and Retention Classes?

 

Yes ViPR CAS supports both retention periods and retention classes and will enforce retention on objects stored on.

 

5b Does ViPR CAS support Advanced Retention Management functionality

 

No.  You cannot use any of the Advanced Retention Management functionality method calls i.e. Event Based retention, Litigation Hold or Min Max retention period governors.

 

5c Can I override retention periods and/or classes?

 

Yes.  ViPR-CAS supports the Privileged Delete capability to be granted at the ViPR CAS Cluster, ViPR CAS Pool and ViPR CAS Application Profile levels as per Centera (Cluster mask, pool mask, profile capabilities).

 

Applications can as before use the FPClip_AuditedDelete() method to delete a clip specifying the FP_OPTION_DELETE_PRIVILEGED option to the call.

 

5d Can I discover the Audited Delete string on deleted C-Clips in ViPR CAS?

 

At present (Oct 2014 - ViPR rev 2.1) you cannot query ViPR CAS for existing or deleted clips.  When this functionality is provided in ViPR CAS you will be able to retrieve the audited delete string from deleted clips.

 

6a Can I migrate C-Clips from an existing Centera to ViPR CAS?

 

ViPR CAS supports the CAS API Raw methods to copy a C-Clip from Centera to ViPR CAS.

 

6b When I create the ViPR CAS Pool to migrate Centera C-Clips to does the ViPR CAS Virtual Pool name need to be the same as the Centera Virtual Pool name?

 

No.  Unlike when migrating to a Centera from another Centera, ViPR CAS does not enforce this.

 

7. Are there any migration service or toolsets that can be used to migrate content from Centera to ViPR CAS?

 

Yes there are a number of 3rd party migration services that can be used to migrate existing Centera content to a ViPR CAS cluster.

 

In addition the ViPR-Sync tool may be of interest to customers who wish to do the migration themselves https://community.emc.com/docs/DOC-38905

 

8 Why does the FPPool_GetPoolInfo() not return the ViPR Replica Node IP addresses?

 

ViPR Services has a different protection and replication mechanisms.  In multiple ViPR Data Centre configurations the separate Primary and Replica paradigm no longer applies.

 

9 Can I create more than one CAS Virtual Pool on my ViPR Cluster

 

Yes, you can create more than one CAS Virtual Pool on your ViPR cluster.  Each can be created in their own ViPR bucket which in turn can be created in a separate ViPR Virtual Pool and ViPR Project.

As with a Centera cluster you can create multiple Access Profiles (with PEA files and Name/Secret pairs) for a CAS Virtual Pool.

 

10 Can I create an Access Profile with read access to multiple CAS Virtual Pools

 

No.  There is no Grant functionality in ViPR CAS so Access Profiles can only have read and write access to one ViPR CAS Pool (the same one before anyone asks).

 

11 How can I test my application with ViPR CAS

 

As with Centera and Atmos CAS, EMC has provided an online internet based ViPR CAS cluster which you can connect to to do your functional testing.  Connectivity details are available at https://community.emc.com/docs/DOC-1038

 

12 Single Instancing of Objects

 

Unlike the Centera object platform the ViPR/ECS object platform does not support single instancing of objects written to it.

 

Migrations

 

1. Can I migrate my existing Centera C-Clips over to ViPR/ECS CAS

 

Yes.  C-Clips on your existing Centera cluster can be migrated to ViPR/ECS via EMC utilities or 3rd Party Solutions.  All of these toolsets use the Raw Method API's to migrate C-Clip and the Content Addresses of the C-Clips are preserved.  This means that the migration only needs to be performed from Centera to ViPR and the application does not need to have any changes to it's Database.

 

2.  Are there any migration issues to be aware of.

 

Not really, but details the team who will do the migration will want to be aware of details like

  • How many C-Clips are on the source cluster
  • What sort of structure has the C-Clip got.  1 blob, 2 blobs, N Blobs, is the Tag/Blob structure of the C-Clip hierarchical?
  • Do all the C-Clips in a Virtual Pool belong to just one Application or more than one Application
  • Does an Application need read access to Virtual Pools that are not its Home Pool (you will need to remap C-Clip in this case).
  • Can you obtain a list of Content Addresses for C-Clips the Application owns?  This is very useful for reconciliation and for the migration process, particularly if more than one Application shares a Virtual Pool e.g. Anonymous profile usage.

 

3. Can I migrate Atmos CAS C-Clips to ViPR/ECS CAS

 

Yes, the Atmos CAS Content Address format is supported by ViPR CAS.

 

4. What are my options for migration

 

vipr-sync

EMC provides an Open Source tool called vipr-sync to provide the migration of content from source to target.  Source and target can be

  • File System local or NAS
  • CAS (Centera, Atmos CAS and/or ViPR CAS)
  • ViPR/ECS
  • Atmos
  • Public Cloud to Private and reverse

 

For more details on vipr-sync please look at https://community.emc.com/docs/DOC-38905

 

There are a number of 3rd Party Migration tools avaialable on the market

 

DataDobi - DobiMiner

 

Datadobi

 

Interlock

 

 

The Archive Migration Specialists | Interlock Technology

 

 

DataTrust

 

EMC Centera Migration Services

 

Seven10 Storage

 

 

 

Seven10 Storage Software |

 

 

 

 

 

Replication

 

1. What are the differences between Centera and ViPR replication.

 

Replication of C-Clips is performed by the underlying ViPR Storage Engine GEOProtection.  If an application attempts to read a C-Clip which is not currently in the VDC which the application is connected to the ViPR Storage Engine will locate the C-Clip on the VDC it is on are retrieve it to the local cache.

 

This means that the FPClip_Exists() will always return success (on Centera the default setting is to not failover the FPClip_Exists call to the replica Centera).

 

The FPPool_ GetInfo() will not return any replica cluster IP addresses.

 

 

 

Further Reading

 

Configure ViPR through the user interface to support applications using the CAS SDK

Configure ViPR through the REST API interface to support applications using the CAS SDK

Manage ViPR CAS pools, clusters, and profiles

Manage ViPR CAS retention

EMC ViPR CAS API Reference (PDF)
EMC ViPR CAS Programmer’s Guide (PDF)