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Explain the NFS server daemons.

62.Explain the NFS server daemons.
Ans.
NFS server needs following daemons:
1. /sbin/rpc.lockd
It starts kernel’s lock manager.

2. /usr/sbin/rpc.mountd
It processes nfs client’s mount requests.

3. /usr/portmap
It allows client’s to discover services available on the NFS server.

4. /sbin/rpc.statd
It manages lock recovery in case of server crash

5. /usr/sbin/rpc.nfsd
It provides all nfs services other than file locking and quotas.

6. /usr/sbin/rpc.rquotad
It provides NFS client’s quota information of NFS exports.

7. rpc.gssd
Creates security contexts on RPC clients for exchanging RPC information using SecureRPC (RPCSEC) using GSS.

8. rpc.svcgssd
Creates security contexts on RPC servers for exchanging RPC information using SecureRPC (RPCSEC) using GSS.

9. rpc.idmapd
Maps local user and group names to NFSv4 IDs (and vice versa).

10. To start the NFS services there are two commands as follows:
#service nfs start
#/etc/rc.d/init.d/nfs.start

11. The startup scripts starts eight copies of nfsd to enable the server to process multiple request simultaneously. If user wants to change this value then edit /etc/sysconfig/nfs and add a line as follow:
RPSNFDCOUNT =n
n will be replaced by the number of nfsd process according to user.
Example:
#cat>/etc/sysconfig/nfs
RPSNFDCOUNT = 16

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