mirror of https://github.com/kubernetes/kops.git
56 lines
2.2 KiB
Markdown
56 lines
2.2 KiB
Markdown
# Kops and etcd
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Kops currently manages etcd using a daemon that runs on the masters called protokube. protokube
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is responsible for:
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* mapping volumes so that exactly one master runs each member of the etcd cluster,
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even when the masters are dynamic (in autoscaling groups).
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* mapping DNS names so that etcd nodes can discover each other even as they move around.
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We are following the [approach recommended by the authors of etcd](https://github.com/coreos/etcd/issues/5418)
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protokube has additional responsibilities also, so we call this the protokube-integrated etcd support.
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Generally, splitting up protokube is part of the general kops roadmap, where we aim to split out our integrated
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tooling into composable tooling that can be upgraded (or even used) separately.
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## Limitations
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The current approach for managing etcd makes certain tasks hard:
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* upgrades/downgrades between etcd versions
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* resizing the cluster
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To address these limitations, we plan to adopt the [etcd-manager](https://github.com/kopeio/etcd-manager) as
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it matures.
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To make adoption easier, the etcd-manager has added a standalone backup tool, that can backup etcd into the
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[expected structure](https://github.com/kopeio/etcd-manager/blob/master/docs/backupstructure.md), even if you are not running the etcd-manager. It should be possible to then use
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the etcd-manager from that backup.
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## Roadmap
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### _kops 1.9_
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* Use the etcd-backup tool to allow users to opt-in to backups with the protokube-integrated etcd support, in the format that etcd-manager expects
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Goal: Users can enable backups on a running cluster.
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### _kops 1.10_
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* Make the etcd-backup tool enabled-by-default, so everyone should have backups.
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* Allow users to opt-in to the full etcd-manager.
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* Make etcd3 the default for new clusters, now that we have an upgrade path.
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Goal: Users that want to move from etcd2 to etcd3 can enable backups
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on an existing cluster (running kops 1.9 or later), then enable the etcd-manager (with kops 1.10 or later).
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### _kops 1.11_
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* Make the etcd-manager the default, deprecate the protokube-integrated approach
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Goal: Users are fully able to manage etcd - moving between versions or resizing their clusters.
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### _untargeted_
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* Remove the protokube-integrated etcd support (_untargeted_)
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