“Error:No space left on device” Is Displayed

Symptom

The following error message is displayed when the cluster is being used:

Error:No space left on device

Cause Analysis

The disk space is insufficient.

Procedure

Run the following command to check the disk usage. The Avail column indicates the available disk space, and the Use% column indicates the percentage of disk space that has been used.

[root@openeuler123 mnt]# df -h
Filesystem                  Size  Used Avail Use% Mounted on
devtmpfs                    255G     0  255G   0% /dev
tmpfs                       255G   35M  255G   1% /dev/shm
tmpfs                       255G   57M  255G   1% /run
tmpfs                       255G     0  255G   0% /sys/fs/cgroup
/dev/mapper/openeuler-root  196G  8.8G  178G   5% /
tmpfs                       255G  1.0M  255G   1% /tmp
/dev/sda2                   9.8G  144M  9.2G   2% /boot
/dev/sda1                    10G  5.8M   10G   1% /boot/efi

The demand for remaining disk space depends on the increase in service data. Suggestions:

-   Check the disk space usage status, ensuring that the remaining space is sufficient for the growth of disk space for over one year.

-   If the disk space usage exceeds 60%, you must clear or expand the disk space.

Run the following command to check the size of the data directory.
```
 du --max-depth=1 -h /mnt/ 
```
The following information is displayed. The first column shows the sizes of directories or files, and the second column shows all the sub-directories or files under the /mnt/ directory.
```
[root@openGauss36 mnt]# du --max-depth=1 -h /mnt
83G	/mnt/data3
71G	/mnt/data2
365G	/mnt/data1
518G	/mnt
```
Clean up the disk space. You are advised to periodically back up audit logs to other storage devices. The recommended log retention period is one month. pg_log stores database process run logs which help database administrators locate faults. You can delete error logs if you view them every day and handle errors in time.
Delete useless data. Back up data that is not used frequently or used for a certain period of time to storage media with lower costs, and clean the backup data to free up disk space.
If the disk space is still insufficient, expand the disk capacity.