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Mounts

Tool Name: disks/mounts

Lists mounted filesystems (device, mount point, type, options) from /proc/thread-self/mounts, sorted by mount point. Read-only. fs_type filters by exact type (ext4, overlay, tmpfs; no globs). It reads the daemon's own mount namespace, so in a container use privileged: true (needs a grant) to get the host's mounts. Text lines look like /dev/sda1 on /mnt type ext4 (rw,...); output_format: json returns an array of objects (device, mount_point, fs_type, options), or null rather than [] when nothing matches (text is then empty). For block devices use disks/list, for the space used on a mount disks/free.

When mcpd runs containerized, passing privileged: true automatically shows the real host's mount table instead of the daemon's own container's - see Master Daemon Configuration's worker.containerized setting.

Arguments​

ArgumentTypeRequiredDescription
fs_typestringnoExact filesystem type, no globs (e.g. 'ext4', 'overlay', 'tmpfs')
output_formatstringnoUse json for structured output (yaml, table and wide return the same JSON); default is text
privilegedbooleannoRun as root. Needs a grant for this tool in mcp-sudo.yaml, otherwise refused

Example​

Every example below shows the equivalent linuxctl command and the raw MCP JSON-RPC call it resolves to. The raw call always follows the same two-step pattern (see MCP API overview for the full explanation): open an SSE stream to get a one-time POST endpoint, then POST the JSON-RPC request there - the result streams back on the SSE connection.

linuxctl
linuxctl get disks mounts

Output:

overlay on / type overlay (rw,relatime,lowerdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1317/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1316/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1315/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1314/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1272/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1271/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1224/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/265/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/264/fs,upperdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1318/fs,workdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshot
...
curl (raw MCP JSON-RPC)
# 1. Open the SSE stream (in the background) and capture the one-time POST endpoint
curl -N -s --cacert mcpd.crt -H "Authorization: Bearer $MCP_TOKEN" https://localhost:9091/sse &
# server sends: event: endpoint / data: /message?session_id=...

# 2. POST the tools/call request to that endpoint
curl -s --cacert mcpd.crt -X POST "https://localhost:9091/message?session_id=<from step 1>" \
  -H "Authorization: Bearer $MCP_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc": "2.0", "id": "1", "method": "tools/call", "params": {"name": "disks/mounts", "arguments": {}}}'

# 3. The result arrives on the SSE stream opened in step 1

Response:

{
  "jsonrpc": "2.0",
  "id": "8",
  "result": {
    "content": [
      {
        "type": "text",
        "text": "overlay on / type overlay (rw,relatime,lowerdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1317/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1316/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1315/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1314/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1272/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1271/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1224/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/265/fs:/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/264/fs,upperdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshots/1318/fs,workdir=/var/lib/containerd/io.containerd.snapshotter.v1.overlayfs/snapshot\n..."
      }
    ]
  }
}