mount.diod - mount diod file systems
mount.diod [OPTIONS] host[:aname] dir [-o options]
is the mount utility for the distributed I/O daemon, which is
an I/O forwarding service for Linux clusters built upon the Linux 9p
performs two main tasks: 1) connect and authenticate to the
server, and 2) issue the mount(2)
system call with
appropriate mount options.
Authentication with the diod
server takes place in user space. The
connected (and authenticated) file descriptor is passed as a mount option to
the kernel 9p
This command requires root to execute the mount(2)
file system must support the 9P2000.L protocol variant, e.g.
kernel 2.6.38 or above.
portion of the mount spec may optionally be supplied in hostlist
format, e.g. host1,host2,host3:aname or host[1-3]:aname, in which case hosts
are tried in order until a successful connection is obtained. Post-connect
mount errors are immediately fatal.
If the host
portion of the mount spec begins with a forward-slash (/), it
refers to the path to a UNIX domain socket.
- -f, --fake-mount
- Do everything except the mount system call.
- -n, --no-mtab
- Do not update the system mtab.
- -v, --verbose
- Set verbose mode.
- -o, --options opt[,opt,...]
- Set mount options (see below).
The following file system specific mount options are handled by
- The aname is the path of the exported file system on the
server. It can be specified in the mount spec in host:aname format
like NFS, or it can be specified with this option. diod will not
allow an attach to an empty aname. diod has a built-in synthetic
control file system that can be mounted with aname of ctl. Note
that "ctl" must be explicitly exported.
- The user name to authenticate to the diod server.
The default is uname=root.
- Select the access mode. access=user (default) causes
the mount to support multiple users, and requires root authentication.
access=<uid> restricts access at the client to only the
- Connect to the diod server on the specified port.
The default is the IANA-assigned 9pfs port 564.
- Select a transport. mount.diod only supports
trans=fd because of its strategy for authentication.
- The file descriptor for reading and writing with
trans=fd. If set, mount.diod assumes this file descriptor is
already connected to a diod server and ignores host in the
device specification, and the port=n option.
- The msize is the max 9P packet payload size. The default is
- Select 9P protocol version. diod only supports
- Specify a caching policy. By default, no caches are used.
If cache=loose, no attempts are made at consistency. This mode is
intended for exclusive, read-only mounts. If cache=fscache, use
FS-Cache for a persistent, read-only cache backend.
- In the context of cache=fscache, select the cache
tag to use for this session. Cache tags for existing cache sessions are
listed in /sys/fs/9p/caches.
- Do not map special files. Represent them as normal files.
This can be used to share devices/named pipes/sockets between hosts.
- Specifies debug level for the kernel 9p module. The debug
level is a bitmask.
0x01 = display verbose error messages
0x02 = developer debug (DEBUG_CURRENT)
0x04 = display 9p trace
0x08 = display VFS trace
0x10 = display Marshalling debug
0x20 = display RPC debug
0x40 = display transport debug
0x80 = display allocation debug
0x100 = display protocol message debug
0x200 = display Fid debug
0x400 = display packet debug
0x800 = display fscache tracing debug
The debug level is global, i.e. it applies to all 9P file systems and it
remains set after the file system is unmounted. The default is