8.14. Troubleshooting Snapshots

Situation

Snapshot creation fails.

Step 1

Check if the bricks are thinly provisioned by following these steps:

Execute the mount command and check the device name mounted on the brick path. For example:
```
mount
```
```
# mount
/dev/mapper/snap_lvgrp-snap_lgvol on /rhgs/brick1 type xfs (rw)
/dev/mapper/snap_lvgrp1-snap_lgvol1 on /rhgs/brick2 type xfs (rw)
```
Copy to Clipboard Toggle word wrap
Run the following command to check if the device has a LV pool name.
```
lvs device-name
```
```
lvs device-name
```
Copy to Clipboard Toggle word wrap
For example:
```
 lvs -o pool_lv /dev/mapper/snap_lvgrp-snap_lgvol
```
```
#  lvs -o pool_lv /dev/mapper/snap_lvgrp-snap_lgvol
   Pool
   snap_thnpool
```
Copy to Clipboard Toggle word wrap
If the Pool field is empty, then the brick is not thinly provisioned.
Ensure that the brick is thinly provisioned, and retry the snapshot create command.

Step 2

Check if the bricks are down by following these steps:

Execute the following command to check the status of the volume:
```
gluster volume status VOLNAME
```
```
# gluster volume status VOLNAME
```
Copy to Clipboard Toggle word wrap
If any bricks are down, then start the bricks by executing the following command:
```
gluster volume start VOLNAME force
```
```
# gluster volume start VOLNAME force
```
Copy to Clipboard Toggle word wrap
To verify if the bricks are up, execute the following command:
```
gluster volume status VOLNAME
```
```
# gluster volume status VOLNAME
```
Copy to Clipboard Toggle word wrap
Retry the snapshot create command.

Step 3

Check if the node is down by following these steps:

Execute the following command to check the status of the nodes:
```
gluster volume status VOLNAME
```
```
# gluster volume status VOLNAME
```
Copy to Clipboard Toggle word wrap
If a brick is not listed in the status, then execute the following command:
```
gluster pool list
```
```
# gluster pool list
```
Copy to Clipboard Toggle word wrap
If the status of the node hosting the missing brick is Disconnected, then power-up the node.
Retry the snapshot create command.

Step 4

Check if rebalance is in progress by following these steps:

Execute the following command to check the rebalance status:
```
gluster volume rebalance VOLNAME status
```
```
gluster volume rebalance VOLNAME status
```
Copy to Clipboard Toggle word wrap
If rebalance is in progress, wait for it to finish.
Retry the snapshot create command.

Situation

Snapshot delete fails.

Step 1

Check if the server quorum is met by following these steps:

Execute the following command to check the peer status:
```
gluster pool list
```
```
# gluster pool list
```
Copy to Clipboard Toggle word wrap
If nodes are down, and the cluster is not in quorum, then power up the nodes.
To verify if the cluster is in quorum, execute the following command:
```
gluster pool list
```
```
# gluster pool list
```
Copy to Clipboard Toggle word wrap
Retry the snapshot delete command.

Situation

Snapshot delete command fails on some node(s) during commit phase, leaving the system inconsistent.

Solution

Identify the node(s) where the delete command failed. This information is available in the delete command's error output. For example:

gluster snapshot delete snapshot1

# gluster snapshot delete snapshot1
Deleting snap will erase all the information about the snap. Do you still want to continue? (y/n) y
snapshot delete: failed: Commit failed on 10.00.00.02. Please check log file for details.
Snapshot command failed

Copy to Clipboard

Toggle word wrap

On the node where the delete command failed, bring down glusterd using the following command:
On RHEL 7 and RHEL 8, run
```
systemctl stop glusterd
```
```
# systemctl stop glusterd
```
Copy to Clipboard Toggle word wrap
On RHEL 6, run
```
service glusterd stop
```
```
# service glusterd stop
```
Copy to Clipboard Toggle word wrap
Important
Red Hat Gluster Storage is not supported on Red Hat Enterprise Linux 6 (RHEL 6) from 3.5 Batch Update 1 onwards. See Version Details table in section Red Hat Gluster Storage Software Components and Versions of the Installation Guide
Delete that particular snaps repository in /var/lib/glusterd/snaps/ from that node. For example:
```
rm -rf /var/lib/glusterd/snaps/snapshot1
```
```
# rm -rf /var/lib/glusterd/snaps/snapshot1
```
Copy to Clipboard Toggle word wrap
Start glusterd on that node using the following command:
On RHEL 7 and RHEL 8, run
```
systemctl start glusterd
```
```
# systemctl start glusterd
```
Copy to Clipboard Toggle word wrap
On RHEL 6, run
```
service glusterd start.
```
```
# service glusterd start.
```
Copy to Clipboard Toggle word wrap
Important
Red Hat Gluster Storage is not supported on Red Hat Enterprise Linux 6 (RHEL 6) from 3.5 Batch Update 1 onwards. See Version Details table in section Red Hat Gluster Storage Software Components and Versions of the Installation Guide
Repeat the 2nd, 3rd, and 4th steps on all the nodes where the commit failed as identified in the 1st step.
Retry deleting the snapshot. For example:
```
gluster snapshot delete snapshot1
```
```
# gluster snapshot delete snapshot1
```
Copy to Clipboard Toggle word wrap

Situation

Snapshot restore fails.

Step 1

Check if the server quorum is met by following these steps:

Execute the following command to check the peer status:
```
gluster pool list
```
```
# gluster pool list
```
Copy to Clipboard Toggle word wrap
If nodes are down, and the cluster is not in quorum, then power up the nodes.
To verify if the cluster is in quorum, execute the following command:
```
gluster pool list
```
```
# gluster pool list
```
Copy to Clipboard Toggle word wrap
Retry the snapshot restore command.

Step 2

Check if the volume is in Stop state by following these steps:

Execute the following command to check the volume info:
```
gluster volume info VOLNAME
```
```
# gluster volume info VOLNAME
```
Copy to Clipboard Toggle word wrap
If the volume is in Started state, then stop the volume using the following command:
```
gluster volume stop VOLNAME
```
```
gluster volume stop VOLNAME
```
Copy to Clipboard Toggle word wrap
Retry the snapshot restore command.

Situation

Snapshot commands fail.

Step 1

Check if there is a mismatch in the operating versions by following these steps:

Open the following file and check for the operating version:
```
/var/lib/glusterd/glusterd.info
```
```
/var/lib/glusterd/glusterd.info
```
Copy to Clipboard Toggle word wrap
If the operating-version is lesser than 30000, then the snapshot commands are not supported in the version the cluster is operating on.
Upgrade all nodes in the cluster to Red Hat Gluster Storage 3.2 or higher.
Retry the snapshot command.

Situation

After rolling upgrade, snapshot feature does not work.

Solution

You must ensure to make the following changes on the cluster to enable snapshot:

Restart the volume using the following commands.

gluster volume stop VOLNAME
gluster volume start VOLNAME

# gluster volume stop VOLNAME
# gluster volume start VOLNAME

Copy to Clipboard

Toggle word wrap

Restart glusterd services on all nodes.
On RHEL 7 and RHEL 8, run
```
systemctl restart glusterd
```
```
# systemctl restart glusterd
```
Copy to Clipboard Toggle word wrap
On RHEL 6, run
```
service glusterd restart
```
```
# service glusterd restart
```
Copy to Clipboard Toggle word wrap
Important
Red Hat Gluster Storage is not supported on Red Hat Enterprise Linux 6 (RHEL 6) from 3.5 Batch Update 1 onwards. See Version Details table in section Red Hat Gluster Storage Software Components and Versions of the Installation Guide

此内容没有您所选择的语言版本。

学习

尝试、购买和销售

社区

关于红帽文档

让开源更具包容性

關於紅帽

Theme

Red Hat legal and privacy links

Red Hat legal and privacy links