Print | Rate this content

HPE MSA 2050 SAN Storage - Isolating Remote Snap Replication Faults

Isolating remote snap replication faults

Remote snap replication is a licensed disaster-recovery feature that performs asynchronous replication of block-level data from a volume in a primary storage system to a volume in a secondary system. Remote Snap creates an internal snapshot of the primary volume, and copies changes to the data since the last replication to the secondary system via iSCSI or FC links. The primary volume exists in a primary pool in the primary storage system. Replication can be completed using either the SMU or CLI.

Replication setup and verification

After storage systems and hosts are cabled for replication, user can use the SMU to prepare to use the Remote Snap feature. Optionally, user can use SSH to access the IP address of the controller module and access the remote snap feature using the CLI.

Basic information for enabling the MSA 2050 SAN controller enclosures for replication supplements the troubleshooting procedures that follow.

  • Familiarize user self with replication content provided in the SMU reference guide.

  • For best practices concerning replication-related tasks, see the technical white paper.

  • In order to replicate an existing volume to a pool on the peer in the primary system or secondary system, follow these steps:

    • Find the port address on the secondary system: Using the CLI, run the show ports command on the secondary system.

    • Verify that ports on the secondary system can be reached from the primary system using either method below:

      • Run the query peer-connection CLI command on the primary system, using a port address obtained from the output of the show ports command above.

      • In the SMU Replications topic, select Action, Query Peer Connection.

    • Create a peer connection.

      To create a peer connection, use the create peer-connection CLI command or in the SMU Replications topic, select Action, Create Peer Connection.

    • Create a replication set.

      To create a replication set, use the create replication-set CLI command or in the SMU Replications topic, select Action, Create Replication Set .

    • Replicate.

      To initiate replication, use the replicate CLI command or in the SMU Replications topic, select Action, Replicate.

top

Diagnostic steps for replication setup

The tables in this sub section show menu navigation for replication using the SMU.

NOTE: Remote Snap must be licensed on all systems configured for replication, and the controller module firmware must be compatible on all systems licensed for replication.

Can user successfully use the Remote Snap feature?

Diagnostics for replication setup: Using remote snap feature
Answer
Possible Reasons
Actions
Yes
System functioning properly.
No action required.
No
Remote Snap is not licensed on each controller enclosure used for replication.
Verify licensing of the optional feature per system:
  • In the Home topic in the SMU, select Action, Install License.

  • The License Settings panel opens and displays information about each licensed feature.

  • If the Replication feature is not enabled, obtain and install a valid license for Remote Snap.

  • For more information on licensing, see the “Installing a license” chapter in the SMU Reference Guide.

No
Compatible firmware revision supporting Remote Snap is not running on each system used for replication.
Perform the following actions on each system used for replication:
  • In the System topic, select Action > Update Firmware. The Update Firmware panel opens. The Update Controller Modules tab shows firmware versions installed in each controller.

  • If necessary, update the controller module firmware to ensure compatibility with other systems.

No
Invalid cabling connection. (If multiple controller enclosures are used, check the cabling for each system)
Verify controller enclosure cabling.
  • Verify use of proper cables.

  • Verify proper cabling paths for host connections.

  • Verify cabling paths between replication ports and switches are visible to one another.

  • Verify that cable connections are securely fastened.

  • Inspect cables for damage and replace if necessary.

No
A system does not have a pool configured.
Configure each system to have a storage pool.

Can user create a replication set?

NOTE: Remote Snap must be licensed on all systems configured for replication, and the controller module firmware must be compatible on all systems licensed for replication.
Diagnostics for replication setup: Creating a replication set
Answer
Possible Reasons
Actions
Yes
System functioning properly.
No action required.
No
On controller enclosures with iSCSI host interface ports, replication set creation fails due to use of CHAP.
Verify licensing of the optional feature per system:
If using CHAP (Challenge-Handshake Authentication Protocol), see the topics about configuring CHAP and working in replications within the SMU reference guide.
No
Unable to create the secondary volume (the destination volume on the pool to which user will replicate data from the primary volume)?1
Perform the following actions on each system used for replication:
  • Review event logs (in the footer, click the events panel and select Show Event List) for indicators of a specific fault in a replication data path component. Follow any Recommended Actions.

  • Verify valid specification of the secondary volume according to either of the following criteria:

    • A conflicting volume does not already exist
    • Available free space in the pool
No
Communication link is down.
Review event logs for indicators of a specific fault in a host or replication data path component.
  • Verify use of proper cables.

  • Verify proper cabling paths for host connections.

  • Verify cabling paths between replication ports and switches are visible to one another.

  • Verify that cable connections are securely fastened.

  • Inspect cables for damage and replace if necessary.

NOTE:
  1. After ensuring valid licensing, valid cabling connections, and network availability, create the replication set using the Replications topic select Action, Create Replication Set.

Can user replicate a volume?

Diagnostics for replication setup: Replicating a volume
Answer
Possible reasons
Actions
Yes
System functioning properly.
No action required.
No
Remote Snap is not licensed on each controller enclosure used for replication.
See actions described in “Can user successfully use the Remote Snap feature?”
No
Non-existent replication set.
  • Determine existence of primary or secondary volumes.

  • If a replication set has not been successfully created, use the replications topic: select Action, Create Replication Set to create one..

  • Review event logs (in the footer, click the events panel and select Show Event List) for indicators of a specific fault in a replication data path component. Follow any Recommended Actions.
No
Network error occurred during in-progress replication.
  • Review event logs for indicators of a specific fault in a replication data path component. Follow any Recommended Actions.

  • Click in the Volumes topic, then click on a volume name in the volumes list. Click the Replication Sets tab to display replications and associated metadata.

  • Replications that enter the suspended state can be resumed manually

No
Communication link is down.
Review event logs for indicators of a specific fault in a host or replication data path component.

Has a replication run successfully?

Diagnostics for replication setup: checking for a successful replication
Answer
Possible Reasons
Actions
Yes
System functioning properly.
No action required.
No
Last successful run shows N/A.
  • In the volumes topic, click on the volume that is a member of the replication set.
    • Select the replication sets table.

    • Check the last successful run information.

  • If a replication has not run successfully, use the SMU to replicate as described in the section about working in the replications topic within the SMU reference guide.
No
Communication link is down.
Review event logs for indicators of a specific fault in a host or replication data path component.

top

Legal Disclaimer: Products sold prior to the November 1, 2015 separation of Hewlett-Packard Company into Hewlett Packard Enterprise Company and HP Inc. may have older product names and model numbers that differ from current models.

Provide feedback

Please rate the information on this page to help us improve our content. Thank you!
Document title: HPE MSA 2050 Storage - Isolating Remote Snap Replication Faults
Document ID: emr_na-a00022428en_us-4
How helpful was this document?
How can we improve this document?
Note: Only English language comments can be accepted at this time.
Please wait while we process your request.