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Installation Guide

Using the snap Problem Determination Tool

The snap command assists you in compiling system configuration information quickly and easily. After this information is compiled, you can view it and compress it for downloading to diskette or tape or for remote transmission. You may be asked by support specialists to execute the snap command to help them accurately identify your system problem.

Note: If you intend to use a tape to send a snap image to IBM for software support, the tape must be in one of the following formats:

Using other formats will prevent or delay IBM software support from being able to examine the contents.

Disk Space Requirements

Approximately 8 MB of temporary disk space is required when executing all of the snap options on an average system. If only one or two options are chosen, the disk space required will be substantially less, depending on the option. The program automatically checks for free space in the /tmp/ibmsupt directory or the directory specified with the -d flag. If there is not enough space, you must expand the file system. You can suppress this check for free space by using the -N option.

Output Directory

The default directory for the output from the snap command is /tmp/ibmsupt. If you want to name an optional directory, use the -d option with the path of your output directory. Each execution of the snap command appends to previously created files.

Execution Permissions

You must have root authority to execute this command.


Use the cleanup option, -r, to remove the information saved by the snap command and to retrieve disk space.


The main options of the snap command are:

-a Gathers information for all of the groups.
-c Creates a pax image of all files in the /tmp/ibmsupt directory tree (or other output directory).

Note: Other information that is not gathered by the snap command can be copied to the snap directory tree before executing the pax command. For example, you might be asked by the support specialist to provide a test case that demonstrates the problem. Copy the test case to the /tmp/ibmsupt directory. When the -c option of the snap command is executed, the test case will be included.
-D Gathers dump and /unix information (the dump device is assumed to be /dev/hd7).
-g Gathers the output of the lslpp -L command. Support specialists use the output to re-create your operating system environment if other problem determination techniques fail. The output is stored in /tmp/ibmsupt/general/lslpp.L. Also, the -g flag gathers general system information and outputs it to the /tmp/ibmsupt/general/general.snap file.
-o Creates a pax file and downloads it to removable media.
-v Displays the output of the commands executed by the snap command.

Before executing the snap -c or snap -o commands, copy any additional information required by the Support Center to the /tmp/ibmsupt/testcase directory (or an alternate directory).

The snap -c and snap -o commands are mutually exclusive. Do not execute both during the same problem-determination session. Use the snap -c command to transmit information electronically. Use the snap -o command to transmit information on a removable output device.

To View the Usage Instructions

For instructions on how to gather information on selected groups (kernel, printer, SNA, NFS, TCP/IP, security, async, language, and file system), enter the snap command (with no options) at the system prompt.


If you think a command started by the snap command is suspended due to an inaccessible server, first press Ctrl+C. Then enter one of the following:

Enter For no action; return to current operation.
s To attempt to kill current operation.
q To quit snap.

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