Removing a CephFS client from the blocklist

In some situations, it can be useful to allow a previously blocklisted Ceph File System (CephFS) client to reconnect to the storage cluster.

Before you begin

Before removing a Ceph File System client, be sure that you have root-level access to the Ceph Monitor node.

About this task

Important: Removing a CephFS client from the blocklist puts data integrity at risk, and does not guarantee a fully healthy, and functional CephFS client as a result. The best way to get a fully healthy CephFS client back after an eviction, is to unmount the CephFS client and do a fresh mount. If other CephFS clients are accessing files that the blocklisted CephFS client was buffering I/O to, it can result in data corruption.

Procedure

Review the blocklist.

For example:

[ceph: root@host01 /]# ceph osd blocklist ls

listed 1 entries
127.0.0.1:0/3710147553 2022-05-09 11:32:24.716146

Remove the CephFS client from the blocklist.

ceph osd blocklist rm CLIENT_NAME_OR_IP_ADDR

For example:

[ceph: root@host01 /]# ceph osd blocklist rm 127.0.0.1:0/3710147553

un-blocklisting 127.0.0.1:0/3710147553

Optional: Set kernel-based CephFS clients automatically to reconnect when removing them from the blocklist.
On the kernel-based CephFS client, set the following option to clean either when doing a manual mount, or automatically mounting with an entry in the /etc/fstab file.
```
recover_session=clean
```
Optional: Set FUSE-based CephFS clients automatically to reconnect when removing them from the blocklist.
On the FUSE client, set the following option to true either when doing a manual mount, or automatically mounting with an entry in the /etc/fstab file.
```
client_reconnect_stale=true
```