thin_migrate(8) System Manager's Manual thin_migrate(8)
NAME
thin_migrate
SYNOPSIS
thin_migrate [options] --source-dev {device} --dest-dev {device}
thin_migrate [options] --source-dev {device} --dest-file {file}
DESCRIPTION
thin_migrate copies provisioned data blocks from a thin device to an-
other device or file. It is designed for cloning a read-only snapshot or
thin volume within a live thin-pool. A metadata snapshot is required to
read the data mappings.
OPTIONS
-h, --help
Print help and exit.
-V, --version
Print version information and exit.
--source-dev {device}
The input read-only thin device to copy.
--dest-dev {device}
The output device as the copy destination.
--dest-file {file}
The output file as the copy destination.
-q, --quit
Suppress output messages, return only exit code.
--buffer-size-meg {size}
Specify the size of the data buffers, in megabytes.
EXAMPLE
Assuming that there's a thin snapshot 'vg/snap' to copy, we must first
set the snapshot to read-only:
$ lvchange vg/snap --permission r
Next, create a metadata snapshot for running thin_migrate:
$ dmsetup message vg-mythinpool-tpool 0 reserve_metadata_snap
Once the metadata snapshot is created, copy the snapshot into another
linear or thin volume. The destination volume must have the same size as
the source device.
$ thin_migrate --src-device /dev/vg/snap --dest-device /dev/vg2/dest
Alternatively, copy the snapshot into a file. thin_migrate can option-
ally create the destination file if it is not present, or the size of
the file will be truncated to match that of the source device.
$ thin_migrate --src-device /dev/vg/snap --dest-file dest.bin
Finally, release the metadata snapshot after thin_migrate finishes its
job:
$ dmsetup message vg-mythinpool-tpool 0 release_metadata_snap
DIAGNOSTICS
thin_migrate returns an exit code of 0 for success or 1 for error.
AUTHOR
Joe Thornber <ejt@redhat.com>
System Manager's Manual Device Mapper Tools thin_migrate(8)
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