Introducing Network File System Version 4 on HP-UX 11i v3

3
Figure 1. COMPOUND RPC request
Figure 1 is an example of an Ethereal trace generated by mounting a file system over NFSv4.
Lines 1 and 2 denote that this is an NFS trace and that the protocol version is 4. Line 3 shows which
NFSv4 RPC the client is making. Because the only other NFSv4 RPC is the NULL RPC, in almost all
cases, the NFSv4 RPC will be the COMPOUND procedure. Lines 4 to 8 provide header information
that describes the RPC. For example, line 4 is a tag describing this as a mount request. COMPOUND
procedures consist of multiple operations, also called opcodes. Line 8 shows that there are five
opcodes present within this request.
The remaining lines are a textual representation of the NFSv4 request. The indentation reflects the
hierarchy of the data. For example, line 16 is indented relative to line 15 because attrmask is a field
within the GETATTR opcode and lines 17 and 18 reflect bits turned on within the attrmask field. There
are more bits turned on (lines 19 and 20) in the attrmask, but they have been replaced with ellipsis to
shorten the output.
Within the COMPOUND request are the opcodes PUTROOTFH, GETFH, LOOKUP, a second GETFH,
and GETATTR appear on lines 9, 10, 11, 14, and 15, respectively. These and all other opcodes are
documented in the IETF RFC 3530 available at http://www.ietf.org/rfc/rfc3530.txt.