Nfs
translates between the Sun network file system protocol (NFS)
and 9P, allowing 9P clients to mount file systems on NFS servers.
NFS servers comprise two separate services: a mount service used to
obtain the initial file handle, and a file service used to perform
actual file system operations.
The Sun port mapper service is typically used to find these two services.
If one address is given, it is taken to be the address of a port mapper service;
nfs
queries the port mapper to find the addresses
of the NFS mount service and file service.
If two addresses are given, the port mapper is bypassed;
addr1
is used as the address of the NFS mount service,
and
addr2
is used as the address of the file service.
The options are:
- -D
- print all 9P messages.
- -R
- print all NFS messages.
- -v
- print verbose information about session startup.
- -p perm
- set the posted service file to have mode
perm,
which is assumed to be octal;
the default is
600.
- -s srvname
- post the service as
/srv/srvname;
the default is
/srv/addr1.
- -u passwd group
- translate user and group names using the
passwd
and
group
files, which are in the traditional Unix format.
The translation is used to present names for
user and group in
stat(5)
and
wstat
messages.
The translation is also used to
choose the user and group credentials
to present for a user.
Without this option, users and groups are presented
as decimal numbers, and everyone attaches as uid -1
(nobody
on most Unix systems).
Portmap
and
nfsmount
are test programs to perform port mapper and NFS mount RPCs.
They
are useful mainly to help debug problems with
starting
nfs
itself.
The
-R
option causes them to print all RPC messages sent and received.
Portmap
queries a Sun RPC portmap server, which maps integer
(program, version, protocol) triples to port numbers.
Program and version are Sun RPC defined, while protocol
is typically TCP (6) or UDP (17).
The commands are:
- null
- a no-op
- dump
- print the entire map
- set prog vers proto port
- add an entry to (or replace an entry in) the map
- unset prog vers proto port
- remove an entry from the map
- getport prog vers proto
- look for an entry with prog, vers, proto
in the map, and return the corresponding port
The default command is
dump.
For running NFS over UDP, there must be an entry
for the NFS v3 mount daemon (100005, 3, 17) and the
NFS v3 server itself (100003, 3, 17).
Nfsmount
queries a Sun NFS mount server, which authenticates (ha!)
connections and hands out file handles naming the root of
an exported file system. This handle is used as the basis
for a conversation with the NFS service daemon itself.
The commands are:
- null
- a no-op
- export
- dump the export table;
each line is a path followed by a list of machines or groups
allowed to mount that path
- mnt path
- attempt to acquire a file handle for path.
the request has user and group id 1001 and
gnot
as the system name.
- umnt path
- notify the mount daemon that a particular path is being
unmounted by the requesting system
- umntall
- notify the mount daemon that all paths mounted by the
requesting system are being unmounted
- dump
- should also dump an export table, but typically
does nothing