Known Issues in DataCore SANsymphony 10.0 PSP20

Asynchronous Replication

Creating a replication on a destination disk already served via loop back might fail and leave both sides on standby or only one side with successful replication. As a workaround, if only one side knows about the replication, perform a forced split and start over. If both are stating standby - activate the one that should be active.

Backups Using DataCore Windows Integration Kit (WIK) VSS Hardware Provider

Backup software running on Windows Hosts with WIK 4.1.2 (or earlier) may fail to create backups as expected when the VSS Hardware Provider component from WIK 4.1.2 is installed. This issue may prevent proper backup creation. As a workaround, use the native VSS provider from the Windows Host OS instead of the VSS Hardware Provider from WIK. Before using the VSS Hardware Provider for offloading snapshot creation as part of the host backup process, check the Release Notes of future WIK releases to verify that this issue is not identified as a Known Issue.

Capacity Optimization on Disk Pools

Capacity Optimization cannot be enabled on a disk pool configured with a sector size of 4KiB. To support capacity optimization on disk pools, the ZFS driver creates Zvols with a sector size of 512B, which are added as physical disks to the disk pool. But the disk pool requires that all physical disks in the pool have the same sector size. As a workaround, configure the disk pool with a sector size of 512B to enable capacity optimization on the disk pool.

Delayed Log Recovery After Parent Server Restart

In an NWAY setup, when the parent server is unplugged and restarted, the full log recovery process takes an unusually long time to complete. Although the recovery eventually occurs, the delay can be significant, negatively impacting overall recovery performance. To temporarily resolve the issue, rescan the ports on both the parent and backup SSV devices to restore normal recovery operations.

Encryption

When encrypted Continuous Data Protection (CDP) enabled or Sequential Storage-enabled virtual disks (vDisks) are imported with the encryption key to a different machine, disable the encryption on them. If re-imported to the parent machine with the encryption key, those vDisks will be in the failed state.

Issues with Multiple PowerShell Connections

Opening too many separate PowerShell connections at the same time can prevent you from connecting to the DataCore Server Group using the DataCore Management Console or from running the Connect-DcsServer PowerShell cmdlet in future attempts.

Workaround: Run PowerShell connections one at a time, making sure to disconnect before starting the next Connect-DcsServer. Alternatively, create a script that uses a single connection to run all queries within the same session.

Log Recovery

Log recovery didn't start after upgrading backup server to PSP19 for Virtual Disk NWAY setup. The log recovery process can be restarted with the two following methods as workaround:

Workaround 1: Once the server is rebooted after the backup upgrade, manually stop and then start the updated server again.

Workaround 2: Follow these steps to restart the log recovery:

  1. On all nodes, navigate to C:\Program Files\DataCore\SANsymphony and run the “dcshadump /dump > outputfile.txt” command in administrative mode using Command Prompt. A new output file will be generated.

  2. In the output file, verify whether there is any line containing "IOsPaused = 1" (under the "TertiaryDevice" section) on all nodes. If you do not find any such lines, this workaround does not apply to your issue, and you should not continue.

  3. Run the dcscaptool.exe /dump DC.txt command (from the same C:\Program Files\DataCore\SANsymphony folder) and locate the WWN name of the updated node in the DC.txt file. For example, the WWN name in the DC.txt file is shown in the image below.

  4. Then, on all other nodes that have a mirror with the updated server, run the “dcscaptool /signalnodestart "updated node WWN" 1” command in administrative mode (from C:\Program Files\DataCore\SANsymphony). Example: “dcscaptool /signalnodestart 227D0030D9CAD4BE 1”.

  5. The log recovery will restart in approximately 2 minutes.

Mirrored Virtual Disks

On a three-way mirrored Virtual Disk (vDisk) configuration, the log recovery does not start following a replace or split-and-unserve on the mirror. As a workaround, rescan the ports.

Purge on Pools with Mirrored Encrypted Virtual Disks

When a disk pool contains a mirrored encrypted virtual disk (vDisk), purging the failed disks in this pool may result in data corruption. Follow the steps below as a workaround:

  1. Disable Auto Recovery for the encrypted mirror vDisk.
  2. Purge the failed disk.
  3. Click Replace on the out-of-sync side.
  4. Enable Auto Recovery for the vDisk.

ReFS-formatted Virtual Disks

Formatting a virtual disk (vDisk) with Microsoft ReFS (Resilient File System) that is mapped over a loopback port will fail with an error stating the drive is not accessible.

Removing DataCore Servers from a Server Group

If the DataCore Server being removed is the controller node of the server group, it may continue to appear in the DataCore Management Console after removal. This occurs because the controller node automatically becomes part of a new, standalone server group once it is removed.

Workaround: To refresh the view and reconnect to the original server group, use either of the following options:

  • The Server Group Connections window, or
  • The Connect to Server Group option from the Common Actions menu.

Replication Issues in SANsymphony on Hyper-V Parent OS May Cause Standby Mode to Get Stuck

When SANsymphony is installed on the Hyper-V parent OS and asynchronous replication is configured for virtual disks, replication may get stuck in standby mode. To temporarily avoid this issue, install SANsymphony on a virtual machine (VM) instead of the parent OS.

Smart Deployment Wizard

  • The Smart Deployment Wizard (SDW) did not start the DataCore Executive Service (DCSX.exe) in the SDW-Clustered Virtual Machines Deployment Scenario after deploying the SANsymphony. As a workaround, check if the DCSX.exe is running in the target server. If not, start it manually and click "re-run" to continue the deployment in the SDW.
  • The Smart Deployment Wizard (SDW) failed to create the NFS share. Intermittently, SDW may fail to create the NFS share for the NAS Clustered configuration menu option and it does not report this failure. As a workaround, create the NFS share manually from Windows server>Failover cluster manager.

Snapshot Issues

  • The Events tab of the Snapshot in the DataCore Management Console may not display the operation completion message of a snapshot update procedure. However, the message does reflect in the DCS trace messaging and may be viewed by the support personnel if necessary. As a workaround, contact DataCore Technical Support for assistance with the trace messaging analysis.
  • When attempting to split a full snapshot, an error is displayed stating that the snapshots are not fully migrated as the migration map percentage is stuck. As a workaround, update the snapshot and retry splitting the snapshot.
  • Promoting a snapshot may fail if the underlying pool is full. The snapshot may not indicate a failed state automatically, and its data might be unreliable. As a workaround, manually delete any snapshots that were attempted to be promoted when the pool was full.

SNMP Output

After deleting the virtual disks (vDisks) and rebooting the servers, the name of some objects may display with extra spacing. This should be a non-functional problem as the object ID remains the same.

Unable to Create 3-Way Virtual Disk with Pass-Through Disks

In the DataCore Management Console, creating a backup storage source using pass-through physical disks is not supported for 3-way virtual disks. Backup storage sources can only be created from disk pools. As a workaround, use disk pools to create the backup storage source instead of pass-through physical disks.