Merge pull request #3954 from ingvagabund/etcd-migrate

Merged by openshift-bot

1 files changed, 53 insertions, 0 deletions

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+Role Name
+=========
+
+Offline etcd migration of data from v2 to v3
+
+Requirements
+------------
+
+It is expected all consumers of the etcd data are not accessing the data.
+Otherwise the migrated data can be out-of-sync with the v2 and can result in unhealthy etcd cluster.
+
+The role itself is responsible for:
+- checking etcd cluster health and raft status before the migration
+- checking of presence of any v3 data (in that case the migration is stopped)
+- migration of v2 data to v3 data (including attaching leases of keys prefixed with "/kubernetes.io/events" and "/kubernetes.io/masterleases" string)
+- validation of migrated data (all v2 keys and in v3 keys and are set to the identical value)
+
+The migration itself requires an etcd member to be down in the process. Once the migration is done, the etcd member is started.
+
+Role Variables
+--------------
+
+TBD
+
+Dependencies
+------------
+
+- etcd_common
+- lib_utils
+
+Example Playbook
+----------------
+
+```yaml
+- name: Migrate etcd data from v2 to v3
+  hosts: oo_etcd_to_config
+  gather_facts: no
+  tasks:
+  - include_role:
+      name: openshift_etcd_migrate
+    vars:
+      etcd_peer: "{{ ansible_default_ipv4.address }}"
+```
+
+License
+-------
+
+Apache License, Version 2.0
+
+Author Information
+------------------
+
+Jan Chaloupka (jchaloup@redhat.com)