Why can't I successfully take snapshots or run Snapshot Replica jobs sometimes?
Last modified date:
2024-03-05
Applicable Products
QTS
Details and Solutions
If you are having trouble taking snapshots or running Snapshot Replica jobs, there may be several possible reasons:
- Hardware limitations
- Snapshots are only supported on thick volumes, thin volumes, and block-based LUNs.
- The NAS must be a x51 model or above, with an Intel or AMD-based CPU and at least 4 GB of memory.
- Each volume or LUN can support a maximum 256 snapshots, with a limit of 1024 snapshots for the entire NAS.
- If you have a x51 NAS model, each volume or LUN can support up to 64 snapshots, with a limit of 256 snapshots for the entire NAS.
- Insufficient storage pool space
- Snapshots require free storage pool space. If there is insufficient space, delete unwanted snapshots.
- Setting the pool guaranteed snapshot space to at least 10% may help prevent this problem.
- Insufficient memory or CPU resources
- If someone is accessing data on the volume or LUN, or if the NAS memory and CPU usages are too high (over 90%), the system may temporarily fail to take snapshots.
- Wait until the system load is lower or disable resource-intensive applications before taking snapshots.
- Insufficient resources on the source and/or destination NAS devices
- When running a Snapshot Replica job, both the source and destination NAS devices must have sufficient space, CPU resources, and memory for a snapshot to be taken and replicated.
- If a Snapshot Replica job fails, ensure there are sufficient resources on both the source and destination NAS devices.
- The source volume or LUN has been expanded
- When running a Snapshot Replica job for the first time, the source volume or LUN is replicated to the remote NAS as a base copy. If the source volume or LUN is subsequently expanded, the copy on the remote NAS will not be able to store new snapshots.
- After expanding a volume or LUN, make sure to delete the snapshot vault on the destination NAS and create a new Snapshot Replica job.
- Certain network ports are blocked
- Snapshot Replica uses SSH port 22 and bbcp data ports 50000 to 62700. Ensure that these ports are not blocked.
