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List and explain all the status files in NFS.

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64.List and explain all the status files in NFS.
Ans.
1. /var/lib/nfs.rmtab – It list each NFS export that is mounted by an NFS client. It uses the Daemon rpc.mountd since it is responsible for servicing the request to mount NFS exports.
Whenever , rpc.mounted daemon receives request, it adds an entry into /var/lib/nfs/rmtab. The same goes for unmounts request but in that case entry is removed from status file.

 2. /var/lib/nfs/etab – It contains list of currently exported filesystem, the exportfs command maintains the entries in this file.

 3. These three scripts which are initialized and controls the required NFS server daemons /etc/rc.d/init.d/portmap
/etc/rc.d/init.d/nfs
/etc/rc.d/init.d/nfslock

 4. The portmap scripts starts the portmap daemon also called as portmapper. All programs that uses RPC, such as NIS and NFS, depends on the information the portmapper provides.

 5. The primary NFS startup script is /etc/rc.d/init.d/nfs, It requires single argument. E.g. start, stop, restart or reloaded. These commands are executed as follows:
#service nfs status
#service nfs stop
#service nfs start
#service nfs restart
#service nfs reload

 6. NFS service also requires the file locking daemons lockd and statd. Lockd is started automatically but statd is started separately. To carry out this process initialization script can also be useful i.e. /etc/rc.d/init.d/nfslock

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