05-16-2005
I'm supposed to write a set of programs that allow users logged on to a host to send messages to each other.
At first, I should start with this messenger program I'm telling you about and add to it a coordination program. Since the coordinator should accept messages from the clients and forward them to all attached clients, I think that the answer to your question is that there will be more than 2 processes communicating between each other.
THANX!!!
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LEARN ABOUT SUSE
rpc.nfsd
rpc.nfsd(8) System Manager's Manual rpc.nfsd(8)
NAME
rpc.nfsd - NFS server process
SYNOPSIS
/usr/sbin/rpc.nfsd [options] nproc
DESCRIPTION
The rpc.nfsd program implements the user level part of the NFS service. The main functionality is handled by the nfsd kernel module. The
user space program merely specifies what sort of sockets the kernel service should listen on, what NFS versions it should support, and how
many kernel threads it should use.
The rpc.mountd server provides an ancillary service needed to satisfy mount requests by NFS clients.
OPTIONS
-d or --debug
enable logging of debugging messages
-H or --host hostname
specify a particular hostname (or address) that NFS requests will be accepted on. By default, rpc.nfsd will accept NFS requests on
all known network addresses. Note that lockd (which performs file locking services for NFS) may still accept request on all known
network addresses. This may change in future releases of the Linux Kernel.
-p or --port port
specify a diferent port to listen on for NFS requests. By default, rpc.nfsd will listen on port 2049.
-N or --no-nfs-version vers
This option can be used to request that rpc.nfsd does not offer certain versions of NFS. The current version of rpc.nfsd can support
both NFS version 2,3 and the newer version 4.
-s or --syslog
By default, rpc.nfsd logs error messages (and debug messages, if enabled) to stderr. This option makes rpc.nfsd log these messages
to syslog instead. Note that errors encountered during option processing will still be logged to stderr regardless of this option.
-T or --no-tcp
Disable rpc.nfsd from accepting TCP connections from clients.
-U or --no-udp
Disable rpc.nfsd from accepting UDP connections from clients.
nproc specify the number of NFS server threads. By default, just one thread is started. However, for optimum performance several threads
should be used. The actual figure depends on the number of and the work load created by the NFS clients, but a useful starting point
is 8 threads. Effects of modifying that number can be checked using the nfsstat(8) program.
Note that if the NFS server is already running, then the options for specifying host, port, and protocol will be ignored. The number of
processes given will be the only option considered, and the number of active nfsd processes will be increased or decreased to match this
number. In particular rpc.nfsd 0 will stop all threads and thus close any open connections.
NOTES
If the program is built with TI-RPC support, it will enable any protocol and address family combinations that are marked visible in the
netconfig database.
SEE ALSO
rpc.mountd(8), exports(5), exportfs(8), rpc.rquotad(8), nfsstat(8), netconfig(5).
AUTHOR
Olaf Kirch, Bill Hawes, H. J. Lu, G. Allan Morris III, and a host of others.
7 Aug 2006 rpc.nfsd(8)