The VMDUMP tool

The VMDUMP tool is a part of z/VM® and does not need to be installed separately.

Dumping with VMDUMP is not destructive. If you dump an operating Linux® instance, the instance continues running after the dump is completed.

VMDUMP can also create dumps for z/VM guests that use z/VM named saved systems (NSS).

VMDUMP has an option for including DCSS content in the dump. Depending on the address range specifications that you use with this option, including DCSS content can considerably increase the dump size. In particular, the dump size can exceed the size of the guest's main memory.

Do not use VMDUMP to dump large z/VM guests; the dump process is very slow. Dumping 1 GB of storage can take up to 15 minutes depending on the used storage server and z/VM version.

For more information on VMDUMP see z/VM: CP Commands and Utilities Reference, SC24-6268.