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V2. This can improve WRITE performance.
6. One procedure was deleted (STATES) and seven were added: ACCESS (check file
access permissions), MKNOD (create a Unix special file), READDIRPLUS
(returns names of files in a directory along with their attributes), FSINFO (returns
the static information about a filesystem), FSSTAT (returns the dynamic
information about a filesystem), PATHCONF (returns the POSIX.1 information
about a file), and COMMIT (commit previous asynchronous writes to stable
storage). 29.8 Summary
RPC is a way to build a client-server application so that it appears that the client just calls
server procedures. All the networking details are hidden in the client and server stubs,
which are generated for an application by the RPC package, and in the RPC library
routines. We showed the format of the RPC call and reply messages, and mentioned that
XDR is used to encode the values, allowing RPC clients and servers to run on machines
with different architectures.
One of the most widely used RPC applications is Sun's NFS, a heterogeneous file access
protocol that is widely implemented on hosts of all sizes. We looked at NFS and the way
that it uses UDP and TCP. Fifteen procedures define the NFS Version 2 protocol.
A client's access to an NFS server starts with the mount protocol, returning a file handle to
the client. The client can then access files on the server's filesystem using that file handle. file:///D|/Documents%20and%20Settings/bigini/Docu...homenet2run/tcpip/tcp-ip-illustrated/nfs_netw.htm (22 of 23) [12/09/2001 14.47.56] Chapter 29. NFS: Network File System Filenames are looked up on the server one element at a time, returning a new file handle
for each element. The end result is a file handle for the file being referenced, which is
used in subsequent reads and writes.
NFS tries to make all its procedures idempotent, so that the client can just reissue a
request if the response gets lost. We saw an example of this with a client reading a file
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This test prep was uploaded on 04/04/2014 for the course ECE EL5373 taught by Professor Guoyang during the Spring '12 term at NYU Poly.
- Spring '12