1cache_writeback(8) System Manager's Manual cache_writeback(8)
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6 cache_writeback - writeback dirty blocks to the origin device.
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9 cache_writeback [options] --metadata-device {device|file} --origin-device {device|file} --fast-device {device|file}
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12 cache_writeback is an offline tool that writes back dirty data to the
13 data device (origin). Intended for use in recovery scenarios when the
14 SSD is giving IO errors.
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16 This tool cannot be run on a live cache.
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19 -h, --help
20 Print help and exit.
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22 -V, --version
23 Print version information and exit.
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25 --metadata-device {device|file}
26 Location of cache metadata.
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28 --origin-device {device|file}
29 Slow device being cached.
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31 --fast-device {device|file}
32 Fast device containing the data that needs to be written back.
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34 --no-metadata-update
35 Do not update the metadata to clear the dirty flags.
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37 You may want to use this flag if you're decommissioning the cache.
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40 --buffer-size-meg {size}
41 Specify the size for the metadata cache.
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43 Defaults to 16 Gig, a larger size may improve performance.
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46 --list-failed-blocks
47 List any blocks that failed the writeback process.
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50 cache_dump(8), cache_check(8), cache_repair(8), cache_restore(8)
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53 Joe Thornber <ejt@redhat.com>
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57System Manager's Manual Device Mapper Tools cache_writeback(8)