Bug 1755557 - Performing disaster recovery twice on a cluster can fail to proceed the second time
Summary: Performing disaster recovery twice on a cluster can fail to proceed the secon...
Alias: None
Product: OpenShift Container Platform
Classification: Red Hat
Component: Etcd
Version: 4.2.0
Hardware: Unspecified
OS: Unspecified
Target Milestone: ---
: 4.2.z
Assignee: Clayton Coleman
QA Contact: ge liu
Depends On: 1755560
Blocks: 1755558
TreeView+ depends on / blocked
Reported: 2019-09-25 16:52 UTC by Clayton Coleman
Modified: 2019-11-13 18:55 UTC (History)
0 users

Fixed In Version:
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Clone Of:
: 1755558 1755560 (view as bug list)
Last Closed: 2019-11-13 18:55:47 UTC
Target Upstream Version:

Attachments (Terms of Use)

System ID Private Priority Status Summary Last Updated
Github openshift machine-config-operator pull 1134 0 'None' 'closed' 'Bug 1755557: Ensure ETCD_INITIAL_CLUSTER is preserved during restore' 2019-11-26 05:50:19 UTC
Red Hat Product Errata RHBA-2019:3303 0 None None None 2019-11-13 18:55:59 UTC

Description Clayton Coleman 2019-09-25 16:52:15 UTC

1. Perform DR steps (remove two masters, wait until quorum lost, physically delete machines)
2. Recover following instructions
3. Repeat 1 but pick a new master (one that was created in step 2)


Able to start a new etcd quorum on the first master with only itself


/usr/local/bin/etcd-snapshot-restore.sh /root/assets/backup/snapshot.db etcd-member-ip-10-0-149-142.ec2.internal=https://etcd-2.ci-ln-shp2psk-d5d6b.origin-ci-int-aws.dev.rhcloud.com:2380

restored the cluster containing the previous (etcd-0, etcd-1) members, preventing further progress.

The root cause is that the etcd-snapshot-restore script accepts ETCD_INITIAL_CLUSTER as an argument, but then sources /run/etcd/environment which may contain the value ETCD_INITIAL_CLUSTER.  So the user's intent was to start a new cluster with one member, but we started with 3 members (including the two that are permanently gone).

The script needs to preserve ETCD_INITIAL_CLUSTER correctly even if it's set in /run/etcd/environment.

Needs to be back ported to all releases.

Comment 2 ge liu 2019-11-05 08:17:59 UTC
Verified on 4.2.0-0.nightly-2019-11-04-231442

Comment 4 errata-xmlrpc 2019-11-13 18:55:47 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.


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