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Nameservers: /etc/resolv.conf
small
$ nslookup
Default Server:  varun.cse.iitb.ernet.in
Address:  144.16.111.26

> bhairav.ee.iitb.ernet.in
Server:  varun.cse.iitb.ernet.in
Address:  144.16.111.26

Name:    bhairav.ee.iitb.ernet.in
Address:  144.16.100.100

> www.ibm.com
Server:  varun.cse.iitb.ernet.in
Address:  144.16.111.26

Non-authoritative answer:
Name:    www.ibm.com
Address:  204.146.18.33

> 202.54.1.1
Server:  varun.cse.iitb.ernet.in
Address:  144.16.111.26

Name:    bom2.vsnl.net.in
Address:  202.54.1.1
}

\nsld{What is NFS?}
\bi
\im A distributed file system that provides transparent access to remote disks.
\im Allows to centralize administration of disks.
\ei

Why do we need NFS ?
\bi 
\im To ensure that files (e.g. home areas) a user needs are accessible from 
local machines.
\im No need to copy files to the local machine.
\ei

\nsld{NFS server}
Important Programs include
\bi
\im {\bf portmap:} Facilitates initial connection 
\im {rpc.mountd:}
\bi
\im Answers NFS access requests
\im Answers file system mount requests
\im Reads the /etc/exports file to determine which file systems to mount
\ei
\im {\bf rpc.nfsd:}
\bi
\im Handles client file system requests
\im Allows the clients read-only and read-write access to file
hierarchy of the server machine.
\ei
\ei

\nsld{/etc/exports File}
\bi
\im Access control list for exporting
\im Sample exports file
{\small
\begin{verbatim}
/home   oswpc-01.cse.iitb.ernet.in(rw)
/home/mtech/rony ankita.cse.iitb.ernet.in(rw,no_root_squash)
The directory /home can be mounted on oswpc-01 in read-write mode. /home/mtech/rony can be mouted in read-write mode on ankita Root on ankita can modify the contents. If the option no_root_squash is not specified then only a user with the same UID can modify the contents of the exported directory.



Sridhar Iyer
2001-01-08