The statistics show which client is making a read request, and the left column shows the time in seconds, with a resolution of about 4 microseconds.
When a read or write request is made, be sure the server doesn't time-out. If it does, the client has to re-send again, and the client's IP code will break up the write block into smaller UDP blocks. The default write time is .07 seconds. The time-out factor is a tunable parameter in the mount command.
# snoop -i pkts -p99,108 99 0.0027 boutique -> sunroof NFS C GETATTR FH=8E6C 100 0.0046 sunroof -> boutique NFS R GETATTR OK 101 0.0080 boutique -> sunroof NFS C RENAME FH=8E6C MTra00192 to .nfs08 102 0.0102 marmot -> viper NFS C LOOKUP FH=561E screen.r.13.i386 103 0.0072 viper -> marmot NFS R LOOKUP No such file or directory 104 0.0085 bugbomb -> sunroof RLOGIN C PORT=1023 h 105 0.0005 kandinsky -> sparky RSTAT C Get Statistics 106 0.0004 beeblebrox -> sunroof NFS C GETATTR FH=0307 107 0.0021 sparky -> kandinsky RSTAT R 108 0.0073 office -> jeremiah NFS C READ FH=2584 at 40960 for 8192
The following table describes the arguments to the snoop command.
Table A-3 Arguments to the snoop Command
-i pkts |
Displays packets previously captured in the pkts file |
-p99,108 |
Selects packets 99 through 108 to be displayed from a capture file; the first number 99, is the first packet to be captured; the last number, 108, is the last packet to be captured; the first packet in a capture file is packet 1 |
The command snoop -i pkts -v 101 obtains more detailed information on packet 101. Table A-4 describes the command arguments.
Table A-4 Description of Arguments to the snoop -i pkts -v 101 Command
-i pkts |
Displays packets previously captured in the pkts file |
-v |
Verbose mode; prints packet headers in detail for packet 101; use this option only when you need information on selected packets |
# snoop -i pkts rpc nfs and sunroof and boutique 1 0.0000 boutique -> sunroof NFS C GETATTR FH=8E6C 2 0.0046 sunroof -> boutique NFS R GETATTR OK 3 0.0080 boutique -> sunroof NFS C RENAME FH=8E6C MTra00192 to .nfs08
This example gives a view of the NFS packets between the systems sunroof and boutique. Table A-5describes the arguments to the previous snoop command.
Table A-5 Arguments to the snoop -i pkts rpc nfs and sunroof and boutique Command
-i pkts |
Displays packets previously captured in the pkts file |
rpc nfs |
Displays packets for an RPC call or reply packet for the NFS protocol; the option following nfs is the name of an RPC protocol from /etc/rpc or a program number |
and |
Performs a logical and operation between two boolean values; for example, sunroof boutique is the same as sunroof and boutique |
Table A-6describes the arguments to the previous snoop command.
Table A-6 Description of Arguments to the snoop -i pkts -o.nfs rpc nfs sunroof boutique Command
-i pkts |
Displays packets previously captured in the pkts file |
-o pkts.nfs |
Saves the displayed packets in the pkts.nfs output file |
rpc nfs |
Displays packets for an RPC call or reply packet for the NFS protocol; the option following nfs is the name of an RPC protocol from /etc/rpc or a program number |
See the snoop man page for additional details on options used with the snoop command and additional information about using snoop.