sshfs: User/group permissions and mapping

[^rooker]

Here are some notes about user/group permission mapping when mounting shares over sshfs.
By default, the uid/gid of the target system are used as-is and not converted or mapped to the connecting client system's users/groups.

In my setup, I wanted to connect from different clients (with different uids/gids), but normalize the permissions of the created files/folders on the sshfs-target to the sshfs-server's uid/gid of the account I'm connecting with.

Here's what my working fstab looks like:

Code: Select all

sshfs#REMOTE_USERNAME@target.server.example:/home/REMOTE_USERNAME/share /mnt/share fuse     noauto,defaults,idmap=user,uid=LOCAL_UID,gid=LOCAL_GID,allow_other,identityfile=/root/.ssh/privatekeyfile   0       0

This does the following:

• Connect to SSH as "REMOTE_USERNAME" on target server "target.server.example"
• Target share is in "/home/REMOTE_USERNAME/share"
• Mounts it on client as "/mnt/share"
• uid/gid on client mountpoint are: LOCAL_UID / LOCAL_GID (use local username/groupname)
• SSH RSA keyfile is in "/root/.ssh/privatekeyfile"
• Files/folders created over this mountpoint are owned by REMOTE_USERNAME/REMOTE_GROUPNAME on the target server

Client system information:

• OS: Debian Jessie (64bit)
• SSHFS: v2.5
• FUSE library: v2.9.3
• FUSE kernel interface: v7.19