nfssvc(2) [mojave man page]

NFSSVC(2)						      BSD System Calls Manual							 NFSSVC(2)

NAME

     nfssvc -- NFS services

SYNOPSIS

     #include <unistd.h>
     #include <nfs/nfs.h>

     int
     nfssvc(int flags, void *argstructp);

DESCRIPTION

     The nfssvc() function is used by the NFS server daemon to pass information into and out of the kernel and also to enter the kernel as a
     server daemon.  The flags argument consists of several bits that show what action is to be taken once in the kernel and the argstructp points
     to any corresponding data that the action may require.

     nfssvc() is called with the flag NFSSVC_NFSD and a NULL argstructp to enter the kernel as an nfsd(8) daemon.  The NFSSVC_NFSD action normally
     does not return until the NFS server is stopped.

     The nfsd(8) server daemon calls nfssvc() with the flag NFSSVC_ADDSOCK and a pointer to a

     struct nfsd_args {
	     int     sock;	     /* Socket to serve */
	     caddr_t name;	     /* Client address for connection based sockets */
	     int     namelen;	     /* Length of name */
     };

     to pass a server side NFS socket into the kernel for servicing by the nfsd(8) daemons.

     The nfsd(8) server daemon calls nfssvc() with the flag NFSSVC_EXPORT and a pointer to a

     struct nfs_export_args {
	     uint32_t		     nxa_fsid;	     /* export FS ID */
	     uint32_t		     nxa_expid;      /* export ID */
	     char		     *nxa_fspath;    /* export FS path */
	     char		     *nxa_exppath;   /* export sub-path */
	     uint32_t		     nxa_flags;      /* export arg flags */
	     uint32_t		     nxa_netcount;   /* #entries in ex_nets array */
	     struct nfs_export_net_args *nxa_nets;   /* array of net args */
     };

     to pass exported file system information into the kernel.

RETURN VALUES

     Upon successful completion, a value of 0 is returned.  Otherwise, -1 is returned the global variable errno is set to specify the error.

ERRORS

     [EPERM]		The caller is not the super-user.

     [EINVAL]		The action specified by the flags argument was not valid.

     [EFAULT]		argstructp points to an invalid address.

     [ENOMEM]		A memory allocation failure prevented the action from completing.

     [EEXIST]		An attempt was made to add a UDP socket via the NFSSVC_ADDSOCK action, but the UDP socket has already been added.

SEE ALSO

     nfsd(8)

HISTORY

     The nfssvc function first appeared in 4.4BSD.

BUGS

     The nfssvc system call is designed specifically for the NFS server daemons and as such is specific to their requirements.	Several fields of
     the argument structures are assumed to be valid, such that nfssvc must be used with extreme care.

BSD
								  January 9, 2007							       BSD

nfsd(8) 						      System Manager's Manual							   nfsd(8)

NAME

       nfsd - The remote NFS compatible server

SYNOPSIS

       /usr/sbin/nfsd [-t num_tcpthreads] [-u num_udpthreads]

       The following form of the nfsd command is not recommended and is supported only for backward compatibility:

       /usr/sbin/nfsd [numthreads]

FLAGS

       Specifies  a  number  of  TCP server threads (per RAD) to spawn.  A value of 8 is recommended as a start.  Specifies a number of UDP server
       threads (per RAD) to spawn.  A value of 8 is recommended as a start.

DESCRIPTION

       The nfsd daemon runs on a server machine to service NFS requests from client machines.  The daemon spawns a number of server  threads  that
       process NFS requests from client machines.  At least one server thread must be running for a machine to operate as a server.

       There  are  two	types of server threads: a server thread that processes NFS requests sent using TCP and a server thread that processes NFS
       requests sent using UDP.  This is necessary because the kernel paths for UDP and TCP NFS messages are different.  The -t  option  specifies
       the number of TCP threads to run and the -u option specifies the number of UDP threads to run.

       On  systems that support Cache Coherent NUMA, the number of threads is per Resource Affinity Domain (RAD).  As you add RADs, the NFS server
       will automatically scale by creating additional threads.  NFS requests are processed by a particular RAD based on the file being  accessed;
       this  confines cached information about a file to a single RAD for efficiency. See numa_intro(3) for more information on the NUMA architec-
       ture.

       If you use the SysMan Menu to configure NFS, it sets the default at 8 UDP and 8 TCP threads.  However, a user can have any  number  of  TCP
       and  UDP  nfsd  threads running up to a maximum of 128 threads.	The optimal number of TCP server threads and UDP server threads depends on
       many factors.  See nfsiod(8) for more information.

       The server threads are implemented as kernel threads; they are part of Process ID 0, not the nfsd process.  The ps  axml  command  displays
       idle server threads under PID 0.  Idle threads will be waiting on nfs_udp_wait or nfs_tcp_wait. Therefore, if 16 server threads are config-
       ured, only one nfsd process is displayed in the output from the ps command,  although  16  server  threads  are	available  to  handle  NFS
       requests.

       Files  that  are larger than 2 gigabytes are exported as 2 gigabyte files when accessed by NFS Version 2.  NFS Version 2 is a 32-bit proto-
       col, therefore, the size and offset fields are 32-bit quantities (on Alpha UFS they are 64-bit  quantities).  Use  caution  when  accessing
       files larger than 2 gigabytes from NFS clients.

EXAMPLES

       In the following example, 16 threads are run (8 for TCP and 8 for UDP): nfsd -t 8 -u 8

FILES

       Specifies  the  command path Specifies the file for logging startup errors (before the server threads are started).  Specifies the file for
       logging NFS errors (after the server threads are started).

RELATED INFORMATION

       Commands: mount(8), mountd(8), nfsconfig(8), nfsstat(8), portmap(8)

       System calls: nfssvc(2) delim off

																	   nfsd(8)