52 lines
1.2 KiB
Markdown
52 lines
1.2 KiB
Markdown
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# Update protocol
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ZFS opens up new methods to safely update the system. These methods are described in this section in combination with general practises to maintain ZFS filesystems.
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## Pre-update
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To be able to rollback the system after a system update one may create a snapshot of the root filesystem.
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```
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# zfs snapshot tank/root/alpine@previous
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```
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> Tip: `zfs destroy` can be used to remove snapshots and `zfs list -t snapshot` can be used to list them.
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## Update
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Perform a system update.
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```
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# apk upgrade
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# reboot
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```
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If the system does not behave accordingly after reboot, one may rollback to the previous snapshot and further investigate from there.
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```
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# zfs rollback -r tank/root/alpine@previous
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```
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## Post-update
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To maintain the performance of the SSDs in the system, perform a trim on the zfs-pool.
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```
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# zpool trim --secure --wait tank
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```
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> Some devices may not support the option `--secure`, remove it then, if necessary.
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Thereafter, perform a scrub on the zfs-pool which checks and repairs the data in the pool.
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```
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# zpool scrub tank
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```
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This may take a while, the progress can be checked with:
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```
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# zpool status tank
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```
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> A ZFS scrub only repairs if mirror or a zraid mode is used in the pool.
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