<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!--Converted with LaTeX2HTML 98.2 beta6 (August 14th, 1998) original version by: Nikos Drakos, CBLU, University of Leeds * revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan * with significant contributions from: Jens Lippmann, Marek Rouchal, Martin Wilck and others --> <HTML> <HEAD> <TITLE>File Handle</TITLE> <META NAME="description" CONTENT="File Handle"> <META NAME="keywords" CONTENT="nfs"> <META NAME="resource-type" CONTENT="document"> <META NAME="distribution" CONTENT="global"> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <LINK REL="STYLESHEET" HREF="nfs.css"> <LINK REL="next" HREF="node7.html"> <LINK REL="previous" HREF="node5.html"> <LINK REL="up" HREF="node5.html"> <LINK REL="next" HREF="node7.html"> </HEAD> <BODY > <!--Navigation Panel--> <A NAME="tex2html91" HREF="node7.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="/usr/lib/latex2html/icons.png/next_motif.png"></A> <A NAME="tex2html89" HREF="node5.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="/usr/lib/latex2html/icons.png/up_motif.png"></A> <A NAME="tex2html83" HREF="node5.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="/usr/lib/latex2html/icons.png/previous_motif.png"></A> <BR> <B> Next:</B> <A NAME="tex2html92" HREF="node7.html">The Kernel-Space NFS Server</A> <B> Up:</B> <A NAME="tex2html90" HREF="node5.html">Interoperability</A> <B> Previous:</B> <A NAME="tex2html84" HREF="node5.html">Interoperability</A> <BR> <BR> <!--End of Navigation Panel--> <H2><A NAME="SECTION00031000000000000000"> File Handle</A> </H2> <P> The definitions of file and file handle are in the NFS V2 protocol are vague. The V2 specification only says a file handle is opaque to client and can contain whatever information the server needs to distinguish an individual file. However, there are many ambiguities: <P> <UL><LI>If 2 file handles from the same server are identical, can clients assume they represent the same file on the server? <P> <LI>If 2 file handles from the same server are different, can clients assume they represent the different files on the server? <P> <LI>Should all the hard links be represented by the same file handle? <P> <LI>When a client renames a file within the same file system, should it expect the file handle is unchanged? </UL> <P> The V2 specification is not clear on them and different NFS implementations interpreted them differently. That leads to the interoperability problems among different NFS implementations. <P> For the interoperability test, we used the Connectathon, which is a network proving ground sponsored by Sun Microsystems for testing software and hardware interoperability allowing vendors to test their interoperability solutions, with special emphasis on NFS and Internet protocols, testsuites, http://www.connectathon.org/nfstests.html, to test the Linux implementation of the NFS V2 Protocol. Solaris 7/x86 and Solaris 7/Sparc are used at the NFS clients. We tested both the user-space and kernel-space NFS servers. <P> As expected, the user-space NFS server didn't support file lock over NFS. All NFS lock tests in the Connectathon testsuites were not performed. Although the rest of tests were ok, the user-space NFS server is not suitable in an environment where the file lock over NFS is required. The later part of this paper will show the performance of the user-space NFS server is not idea either. <P> <HR> <!--Navigation Panel--> <A NAME="tex2html91" HREF="node7.html"> <IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="/usr/lib/latex2html/icons.png/next_motif.png"></A> <A NAME="tex2html89" HREF="node5.html"> <IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="/usr/lib/latex2html/icons.png/up_motif.png"></A> <A NAME="tex2html83" HREF="node5.html"> <IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="/usr/lib/latex2html/icons.png/previous_motif.png"></A> <BR> <B> Next:</B> <A NAME="tex2html92" HREF="node7.html">The Kernel-Space NFS Server</A> <B> Up:</B> <A NAME="tex2html90" HREF="node5.html">Interoperability</A> <B> Previous:</B> <A NAME="tex2html84" HREF="node5.html">Interoperability</A> <!--End of Navigation Panel--> <ADDRESS> <I>H.J. Lu</I> <BR><I>1999-08-15</I> </ADDRESS> </BODY> </HTML>
