Время создания: 27.09.2017 10:20
Текстовые метки: ssh sshfs
SSHFS is a FUSE-based filesystem client for mounting directories over SSH.
4.3Secure user access
5.2Connection reset by peer
5.3Remote host has disconnected
5.4Freezing apps (e.g. Gnome Files, Gedit)
5.5fstab mounting issues
Install the sshfs package.
If you often need to mount sshfs filesystems you may be interested in using an sshfs helper, such as qsshfsAUR, sftpman, sshmntAUR or fmount.py.
You may want to use Google Authenticator providing additional security as in two-step authentication.
SSH keys may be used over traditional password authentication.
In order to be able to mount a directory the SSH user needs to be able to access it. Invoke sshfs to mount a remote directory:
$ sshfs [user@]host:[dir] mountpoint [options]
$ sshfs myuser@mycomputer:/remote/path /local/path -C -p 9876
Here -p 9876 specifies the port number and -C enables compression. For more options see the #Options section.
When not specified, the remote path defaults to the remote user home directory. Default user names and options can be predefined on a host-by-host basis in ~/.ssh/config to simplify the sshfs usage. For more information see Secure Shell#Client usage.
SSH will ask for the password, if needed. If you do not want to type in the password multiple times a day, see SSH keys.
To unmount the remote system:
$ fusermount -u local_mount_point
$ fusermount -u /mnt/sessy
sshfs can automatically convert between local and remote user IDs. Use the idmap=user option to translate the UID of the connecting user to the remote user myuser (GID remains unchanged):
$ sshfs myuser@mycomputer:/remote/path /local/path -o idmap=user
If you need more control over UID and GID translation, look at the options idmap=file, uidfile and gidfile.
You may want to restrict a specific user to a specific directory on the remote system. This can be done by editing /etc/ssh/sshd_config:
Match User someuser
Note: The chroot directory must be owned by root, otherwise you will not be able to connect.
See also SFTP chroot. For more information check the sshd_config(5) man page for Match, ChrootDirectory and ForceCommand.
This article or section is out of date.
Reason: This requires to install fuse2 for mount.fuse, or create a symbolic link from mount.fuse3. See FS#55564 (Discuss in Talk:SSHFS#)
Automounting can happen on boot, or on demand (when accessing the directory). For both, the setup happens in the fstab.
Note: Keep in mind that automounting is done through the root user, therefore you cannot use hosts configured in .ssh/config of your normal user.
To let the root user use an SSH key of a normal user, specify its full path in the IdentityFile option.
And most importantly, use each sshfs mount at least once manually while root so the host's signature is added to the /root/.ssh/known_hosts file.
This article or section needs expansion.
Reason: Is there a way to make this work with a passphrase-protected private key? E.g. it prompts for the passphrase at first access. Alternatively, clearly state that it's not possible and why. (Discuss in Talk:SSHFS#)
With systemd on-demand mounting is possible using /etc/fstab entries.
user@host:/remote/folder /mount/point fuse.sshfs noauto,x-systemd.automount,_netdev,users,idmap=user,IdentityFile=/home/user/.ssh/id_rsa,allow_other,reconnect 0 0
The important mount options here are noauto,x-systemd.automount,_netdev.
noauto tells it not to mount at boot
x-systemd.automount does the on-demand magic
_netdev tells it that it is a network device, not a block device (without it "No such device" errors might happen)
Note: After editing /etc/fstab, (re)start the required service: systemctl daemon-reload && systemctl restart <target> where <target> can be found by running systemctl list-unit-files --type automount
Tip: autosshfs-gitAUR do not require editing /etc/fstab to add a new mountpoint. Instead, regular users can create one by simply attempting to access it (with e. g. something like ls ~/mnt/ssh/[user@]yourremotehost[:port]). autosshfs-gitAUR uses AutoFS. Users need to be enabled to use it with autosshfs-user.
An example on how to use sshfs to mount a remote filesystem through /etc/fstab
USERNAME@HOSTNAME_OR_IP:/REMOTE/DIRECTORY /LOCAL/MOUNTPOINT fuse.sshfs defaults,_netdev 0 0
Take for example the fstab line
email@example.com:/home/llib/FAH /media/FAH2 fuse.sshfs defaults,_netdev 0 0
The above will work automatically if you are using an SSH key for the user. See Using SSH Keys.
If you want to use sshfs with multiple users:
firstname.lastname@example.org:/home/user /media/user fuse.sshfs defaults,allow_other,_netdev 0 0
Again, it is important to set the _netdev mount option to make sure the network is available before trying to mount.
Secure user access
When automounting via fstab, the filesystem will generally be mounted by root. By default, this produces undesireable results if you wish access as an ordinary user and limit access to other users.
An example mountpoint configuration:
USERNAME@HOSTNAME_OR_IP:/REMOTE/DIRECTORY /LOCAL/MOUNTPOINT fuse.sshfs noauto,x-systemd.automount,_netdev,user,idmap=user,follow_symlinks,identityfile=/home/USERNAME/.ssh/id_rsa,allow_other,default_permissions,uid=USER_ID_N,gid=USER_GID_N 0 0
Summary of the relevant options:
allow_other - Allow other users than the mounter (i.e. root) to access the share.
default_permissions - Allow kernel to check permissions, i.e. use the actual permissions on the remote filesystem. This allows prohibiting access to everybody otherwise granted by allow_other.
uid, gid - set reported ownership of files to given values; uid is the numeric user ID of your user, gid is the numeric group ID of your user.
Read the SSH Checklist Wiki entry first. Further issues to check are:
1. Is your SSH login sending additional information from server's /etc/issue file e.g.? This might confuse SSHFS. You should temporarily deactivate server's /etc/issue file:
$ mv /etc/issue /etc/issue.orig
2. Keep in mind that most SSH related troubleshooting articles you will find on the web are not Systemd related. Often /etc/fstab definitions wrongly begin with sshfs#user@host:/mnt/server/folder ... fuse ... instead of using the syntax user@host:/mnt/server/folder ... fuse.sshfs ... x-systemd, ....
3. Check that the owner of server's source folder and content is owned by the server's user.
$ chown -R USER_S: /mnt/servers/folder
4. The server's user ID can be different from the client's one. Obviously both user names have to be the same. You just have to care for the client's user IDs. SSHFS will translate the UID for you with the following mount options:
5. Check that the client's target mount point (folder) is owned by the client user. This folder should have the same user ID as defined in SSHFS's mount options.
$ chown -R USER_C: /mnt/client/folder
6. Check that the client's mount point (folder) is empty. By default you cannot mount SSHFS folders to non-empty folders.
7. If you want to automount SSH shares by using an SSH public key authentication (no password) via /etc/fstab, you can use this line as an example:
USER_S@SERVER:/mnt/on/server /nmt/on/client fuse.sshfs x-systemd.automount,_netdev,user,idmap=user,transform_symlinks,identityfile=/home/USER_C/.ssh/id_rsa,allow_other,default_permissions,uid=USER_C_ID,gid=GROUP_C_ID,umask=0 0 0
Considering the following example settings ...
SERVER = Server host name (serv) USER_S = Server user name (pete) USER_C = Client user name (pete) USER_S_ID = Server user ID (1004) USER_C_ID = Client user ID (1000) GROUP_C_ID = Client user's group ID (100)
you get the client user's ID and group ID with
$ id USERNAME
this is the final SSHFS mount row in /etc/fstab;
pete@serv:/mnt/on/server /nmt/on/client fuse.sshfs x-systemd.automount,_netdev,user,idmap=user,transform_symlinks,identityfile=/home/pete/.ssh/id_rsa,allow_other,default_permissions,uid=1004,gid=1000,umask=0 0 0
8. If you know another issue for this checklist please add it the list above.
Connection reset by peer
If you are trying to access the remote system with a hostname, try using its IP address, as it can be a domain name solving issue. Make sure you edit /etc/hosts with the server details.
If you are using non-default key names and are passing it as -i .ssh/my_key, this will not work. You have to use -o IdentityFile=/home/user/.ssh/my_key, with the full path to the key.
If your /root/.ssh/config is a symlink, you will be getting this error as well. See this serverfault topic
Adding the option 'sshfs_debug' (as in 'sshfs -o sshfs_debug user@server ...') can help in resolving the issue.
If that doesn't reveal anything useful, you might also try adding the option 'debug'
If you are trying to sshfs into a router running DD-WRT or the like, there is a solution here. (note that the -osftp_server=/opt/libexec/sftp-server option can be used to the sshfs command in stead of patching dropbear)
Old Forum thread: sshfs: Connection reset by peer
Make sure your user can log into the server (especially when using AllowUsers)
Make sure Subsystem sftp /usr/lib/ssh/sftp-server is enabled in /etc/ssh/sshd_config.
Note: When providing more than one option for sshfs, they must be comma separated. Like so: 'sshfs -o sshfs_debug,IdentityFile=</path/to/key> user@server ...')
Remote host has disconnected
If you receive this message directly after attempting to use sshfs:
First make sure that the remote machine has sftp installed! It will not work, if not.
Then, check that the path of the Subsystem sftp in /etc/ssh/sshd_config on the remote machine is valid.
Freezing apps (e.g. Gnome Files, Gedit)
Warning: This prevents the recently used file list from being populated and may lead to possible write errors.
If you experience freezing/hanging (stopped responding) applications, you may need to disable write-access to the ~/recently-used.xbel file.
# chattr +i /home/USERNAME/.local/share/recently-used.xbel
See the following bug report for more details and/or solutions.
fstab mounting issues
To get verbose debugging output, add the following to the mount options:
Note: Here, \040 represents a space which fstab uses to separate fields.
To be able to run mount -av and see the debug output, remove the following:
Так же в этом разделе: