File System (System Admin)

Create and manage CephFS-based file systems. Subvolumes, snapshots, schedules, and credentials provide POSIX-compatible file storage.

• Navigation path: Storage Admin › File › File systems
• Search: Search file systems by attributes (default filter key: Name)

List Screen

Sidebar (SNB)

Use the left sidebar to move to each Storage Admin screen (Cluster·Block·File·Object·Monitoring).

No.	Feature	Item	Description
1-1	Dashboard	Dashboard	· Inventory·Capacity·Cluster utilization summary.
1-2	Pools	Pools	· View Ceph storage pools·PGs.
1-3	Hosts	Hosts	· Storage node hardware·OSD configuration.
1-4	OSDs	OSDs	· Object Storage Daemon status·capacity.
1-5	Physical disks	Physical disks	· View physical disks·Identify.
1-6	Images	Images	· RBD block images.
1-7	File systems	File systems	· CephFS file systems.
1-8	Buckets	Buckets	· System-wide S3 buckets.
1-9	Overall performance	Overall performance	· Pools·OSDs·Hosts·Images performance metrics.

Search · Create

Search file systems or create a new one.

No.	Feature	Item	Description
2-1	Search	Search	· Search by name, etc.
2-2	Create	Create file system	· Open the new CephFS file system creation drawer.

List table

CephFS file system list.

No.	Feature	Item	Description
3-1	Columns	Name / Status	File system name / status.
		MDS	Metadata Server status.
		Usage / Clients / Throughput	Usage·connected clients·throughput.
		Action	Authorize / Edit / Delete.

Default sort is Name ascending. Search filters support Name (text input) and Status (select: Enabled/Disabled).

Deletion Constraint

File systems in Enabled (Active) state cannot be deleted (row action Delete disabled). Shut down the file system first to disconnect all clients, then delete it. — "Shut down the file system and disconnect all clients before deleting."

Create

Create a new CephFS file system by specifying a name, Placement, and hosts.

Create entry

Clicking opens the creation drawer.

Create drawer

Create a CephFS file system by specifying name·placement·hosts.

No.	Feature	Item	Description
2-1	Name	File System Name *	· File system name.
2-2	Placement	Placement *	· MDS placement method (including whether to use an existing pool).
2-3	Hosts	Hosts *	· Select the hosts to place the MDS on.
2-4	Create / Cancel	Create / Cancel	· Create: create. Cancel: close.

Authorize

Use the row action Authorize to grant directory access permissions to a specific user (CephX).

Authorize entry (row action)

Select Authorize from the row menu.

Authorize drawer

Grant a specific user access to a file system directory.

No.	Feature	Item	Description
2-1	User	User Id *	· User ID to grant permission to.
2-2	Directory	Directory *	· Directory path to allow access to.
2-3	Permissions	Permissions	· Read·Write·Quota·Snapshot·Rootsquash permission options.
2-4	Authorize / Cancel	Authorize / Cancel	· Authorize: grant permission. Cancel: close.

Edit

Use the row action Edit to view and modify the file system name and associated pools (Data/Metadata).

Edit entry (row action)

Select Edit from the row menu.

Edit drawer

Review and edit the file system name and linked pools (Data/Metadata).

No.	Feature	Item	Description
2-1	Name	Name *	· File system name.
2-2	Pool	Data pool / Metadata Pool	· Linked data·metadata pools.
2-3	Save / Cancel	Save / Cancel	· Save or close.

File System Detail

Click a file system name to open the detail screen.

Header Information

Item	Description
Status	Enabled (green badge) / Disabled (gray badge)
Usage	ProgressBar + n% (used/total)
MDS	{active} active / {standby} standby
Clients	Number of connected clients
Created at	Creation timestamp

Use the Edit / Delete buttons at the top to edit or delete.

The detail screen consists of eight tabs.

Tab	Description
Details	MDS Ranks, Standbys, Pools information
Directories	Per-directory quotas and snapshots
Subvolumes	Create and manage subvolumes
Snapshots	File system-level snapshots
Schedules	Automatic snapshot schedules
Clients	Connected client list
Credentials	CephX user permissions and mount guide
Performance	Real-time performance metrics

Details Tab

View the file system's MDS configuration and pool information.

Ranks Section

Column	Description
Rank	MDS rank number (sortable)
State	MDS state (e.g., active, standby). Displayed as badge
Daemon	Daemon name (sortable)
Activity	Work description
Dentries	Directory entry cache count (sortable)
Inodes	Inode cache count (sortable)
Dirs	Directory count (sortable)
Caps	Issued capability count (sortable)

Default sort is Rank ascending. Shows 5 rows per page.

Standbys Section

Column	Description
Daemon	Standby MDS daemon name

No default sort (server return order). Shows 5 rows per page.

Pools Section

Column	Description
Pool	Pool name (sortable)
Type	data or metadata
Size	Total capacity (sortable, e.g., 70.2 TiB)
Used	Used capacity (sortable, e.g., 17.6 TiB)
Usage	ProgressBar + percentage (e.g., 25%)

Default sort is Pool name ascending. Shows 5 rows per page.

Directories Tab

Manage per-directory quotas and snapshots.

Quotas

Item	Description
Max bytes	Maximum bytes (0 = no limit → "No limit")
Max files	Maximum file count (0 = no limit → "No limit")

Use the Edit quota button to change quotas (opens drawer).

Snapshots

Create and manage directory-level snapshots.

Column	Description
Name	Snapshot name (sortable)
Path	Snapshot path
Created	Creation timestamp (sortable)

Default sort is Created descending (newest first). Shows 10 rows per page.

Search filters: Name (text input), Path (text input), Created at (date range)

Subvolumes Tab

Create and manage subvolumes. A subvolume is an isolated volume within the file system with its own POSIX permissions and quotas.

Column	Description
Name	Subvolume name (sortable)
Mode	POSIX permissions — displayed as 3 badges (e.g., owner: rwx, group: r-x, others: rw-)
Usage	Capacity utilization (ProgressBar + percentage, sortable). Shows ∞ when no total is set
Path	Mount path (monospace font + Copy button)
Data pool	Data pool name (sortable)
Created at	Creation timestamp (sortable)

Default sort is creation date descending (newest first). Shows 10 rows per page.

Subvolume Actions

Action	Description
Attach	Attach the subvolume (opens modal)
Mount command	Show the mount command in code font (copyable)
CephX key	Show the authentication key. Default masked → Show/Hide toggle. Copy button always copies the full key
Resize	Change subvolume size (opens drawer)
Delete	Delete the subvolume

Caution

Subvolumes with existing snapshots cannot be deleted.

Tooltip: "Delete all snapshots before deleting this subvolume."

Mount command example:

sudo mount -t ceph :/{path} /mnt/{name} -o name=client.{fs},fs={fs}

Snapshots Tab

Manage file system-level snapshots.

Column	Description
Name	Snapshot name (sortable). Naming convention: {subvolume_name}-snap-yyyymmdd
Subvolume	Parent subvolume name
Pending clones	In-progress clone operations. Shows "No" badge when none, or clone name badges when present
Created	Creation timestamp (sortable)

Default sort is Created descending (newest first). Shows 10 rows per page.

Snapshot Actions

Action	Description
Create subvolume from snapshot	Create a new subvolume from a snapshot (opens drawer)
Delete	Delete the snapshot (shows modal)

Schedules Tab

Manage automatic snapshot creation schedules.

Column	Description
Subvolume	Target subvolume name (sortable)
Status	Active (green badge) / Inactive (gray badge)
Frequency	Snapshot creation interval (e.g., Every 1 day)
Start	Start time
Retention	Retention policy. Displayed as badges (e.g., daily: 7, weekly: 4)
Last run	Last execution time. Shows "-" when never run

Default sort is Created at descending (newest first). Shows 10 rows per page.

Schedule Actions

Action	Description
Create	Create a new schedule (opens drawer)
Edit	Edit an existing schedule (opens drawer)
Delete	Delete a schedule (shows modal)

Clients Tab

View the list and status of clients connected to the file system.

Credentials Tab

View the CephX users (entities) authorized to access the file system, modify or revoke their permissions, and access the mount guide.

Search Filters

Filter	Type
User ID	Text
Directory	Text

Entering text without selecting a filter key automatically applies the User ID filter.

Table

Column	Description
User ID	CephX entity name (client.<name> format, sortable)
Directory	Authorized CephFS directory path (monospace font + Copy button)
Permissions	Granted permissions as badges: Read, Write, Quota, Snapshot, Rootsquash
Key	CephX keyring value. Default masked. Show/Hide toggle. Copy button always copies the full key
Created	Creation timestamp (sortable)

Default sort is User ID ascending (A→Z). Shows 10 rows per page.

Credentials Actions

Action	Description
Authorize	Grant access permissions to a CephX user (opens drawer)
Mount guide	Show the mount guide modal
Edit	Edit permissions (opens drawer)
Delete	Delete the credential (shows confirmation modal)

Credential Deletion

Deleting a credential interrupts all in-progress I/O for that user.

"Evicting this client interrupts all in-progress I/O."

Mount Guide Modal

Click the Mount guide action on a row in the Credentials tab to view mount information for that CephX user.

The modal displays the following information.

User ID — Selected CephX user ID (read-only)

ceph.conf — Cluster configuration (code block)

[global]
fsid = <cluster-fsid>
mon_host = <mon-addr-1>,<mon-addr-2>,<mon-addr-3>

Save to /etc/ceph/ceph.conf on the client machine.

Keyring — Full keyring file contents (code block)

[client.<vol_name>.<subvol_name>]
    key = <AQBx...==>
    caps mon = "allow r fsname=<vol_name>"
    caps mds = "allow rw fsname=<vol_name> path=/volumes/_nogroup/<subvol_name>/<uuid>"
    caps osd = "allow rw pool=cephfs.<vol_name>.data namespace=fsvolumens___nogroup_<subvol_name>"

Save to /etc/ceph/ceph.client.<name>.keyring on the client machine (file permission 600).

Keyring File Required

VM kernel mount will not work if the keyring file does not exist in /etc/ceph/. mount.ceph automatically finds the keyring file corresponding to the -o name= client ID at the standard path and reads the secret key.

Mount command — Three mount methods are provided as tabs.

Tab	Method	Description
Kernel	mount -t ceph	Direct OSD distributed I/O, best performance. Requires ceph-common
FUSE	ceph-fuse	Alternative when kernel module/version constraints exist. Requires ceph-fuse
Kubernetes	CSI (ceph-csi-cephfs)	PV/PVC-based automation, static provisioning

Each tab's code block is dynamically generated with the selected CephX user's information.

Mount Information

Share this information with the user who needs to mount the file system. For detailed setup instructions, see the mount guide documentation.

Access Restriction

Each keyring is restricted to its authorized directory. Attempting to mount an unauthorized path returns permission denied.

VM Mount — Kernel (mount -t ceph)

Prerequisites:

Item	Requirement
OS	Linux (kernel 4.x+, Ubuntu 22.04 recommended)
Package	ceph-common (includes mount.ceph)
Network	MON 3300/6789, OSD 6800-7300 reachable
Auth files	/etc/ceph/ceph.conf · /etc/ceph/ceph.client.<vol>.<subvol>.keyring

# Ubuntu / Debian
sudo apt install -y ceph-common

# RHEL / CentOS
sudo yum install -y ceph-common

Mount command:

sudo mkdir -p /mnt/${VOL_NAME}
sudo mount -t ceph \
  ${VOL_NAME}.${SUBVOL_NAME}@.${VOL_NAME}=/volumes/_nogroup/${SUBVOL_NAME}/${SUBVOL_UUID} \
  /mnt/${VOL_NAME} \
  -o name=${VOL_NAME}.${SUBVOL_NAME}

FSID can be omitted when /etc/ceph/ceph.conf includes fsid.

Persistent mount (/etc/fstab):

<vol>.<subvol>@.<vol>=/volumes/_nogroup/<subvol>/<uuid>  /mnt/<vol>  ceph  name=<vol>.<subvol>,noatime,_netdev  0  0

VM Mount — FUSE (ceph-fuse)

Use when kernel mount is difficult due to kernel module/version constraints.

sudo mkdir -p /mnt/${VOL_NAME}
sudo ceph-fuse /mnt/${VOL_NAME} \
  --id ${VOL_NAME}.${SUBVOL_NAME} \
  --conf /etc/ceph/ceph.conf \
  --keyring /etc/ceph/ceph.client.${VOL_NAME}.${SUBVOL_NAME}.keyring \
  --client_fs ${VOL_NAME} \
  -r /volumes/_nogroup/${SUBVOL_NAME}/${SUBVOL_UUID}

Option	Description
--id	CephX client ID (without client.)
--client_fs	CephFS FileSystem name
-r	Restrict mount root to the subvolume path
--keyring	Keyring path (can be omitted if at standard path)

Pod Mount — Kubernetes CSI

In Kubernetes environments, use the ceph-csi-cephfs CSI driver for PV/PVC-based mounting.

Prerequisites:

Item	Requirement
Kubernetes	K8s 1.25+
CSI driver	ceph-csi-cephfs Helm chart (v3.14+)
Network	Worker nodes → MON/OSD reachable

Secret creation:

apiVersion: v1
kind: Secret
metadata:
  name: csi-cephfs-secret
  namespace: ceph-csi-cephfs
type: Opaque
stringData:
  userID: "<vol_name>.<subvol_name>"
  userKey: "<key value>"

PV/PVC creation (static provisioning):

apiVersion: v1
kind: PersistentVolume
metadata:
  name: <subvol_name>
spec:
  capacity:
    storage: 10Gi
  accessModes: [ReadWriteMany]
  persistentVolumeReclaimPolicy: Retain
  csi:
    driver: cephfs.csi.ceph.com
    volumeHandle: <subvol_name>
    volumeAttributes:
      clusterID: "<cluster-fsid>"
      fsName: "<vol_name>"
      rootPath: "/volumes/_nogroup/<subvol_name>/<uuid>"
      staticVolume: "true"
    nodeStageSecretRef:
      name: csi-cephfs-secret
      namespace: ceph-csi-cephfs
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: <subvol_name>
spec:
  storageClassName: ""
  accessModes: [ReadWriteMany]
  resources:
    requests:
      storage: 10Gi
  volumeName: <subvol_name>

Mount Verification

df -h /mnt/${VOL_NAME}
echo "hello cephfs $(date)" | sudo tee /mnt/${VOL_NAME}/test.txt
cat /mnt/${VOL_NAME}/test.txt

Performance Tab

Monitor real-time performance metrics for the file system.

Next steps

• Pools — Data pool management
• Overall Performance — Cluster-wide performance monitoring