Description of problem: etcd writes get blocked when the etcd_quota_backend_quota was hit. Version-Release number of selected component (if applicable): OpenShift: 3.6.173.0.5 etcd: 3.1.9 Actual results: etcdctl3 alarm list etcdctl3 endpoint status showed hitting the 2GB limit
The default quota is 2GB which we hit on us-east-1 and were very close to us-west-2 and us-west-1. We increased the limit to 4Gb. We should increase the limit out of the box to 8GB for all starter clusters (which is the etcd3 maximum) and add alerting to warn us when we cross the 4GB threshold. For end users, we should probably increase the default to 4Gb or 8Gb and also recommend alerting on the size value. The size of the /var/lib/etcd/member/db file should be very close to the internal size, and it's likely we can report on that as a proxy if it is simpler.
Hard quota blocks all writes when hit, which means the cluster goes into a hold state until the quota is increased.
It looks like we're not doing anything to compact old revisions as outlined in the etcd maintenance documentation. Shouldn't we be enabling that so that we don't grow unbounded? Relevant config vars from that cluster ETCD_QUOTA_BACKEND_BYTES=4294967000 ETCD_DATA_DIR=/var/lib/etcd/ ETCD_SNAPSHOT_COUNT=60000 ETCD_HEARTBEAT_INTERVAL=2000 ETCD_ELECTION_TIMEOUT=20000 ETCD_DEBUG=false ETCD_LOG_PACKAGE_LEVELS="*=INFO" https://coreos.com/etcd/docs/latest/op-guide/maintenance.html
Upstream PR: https://github.com/openshift/openshift-ansible/pull/5518
Commit pushed to master at https://github.com/openshift/openshift-ansible https://github.com/openshift/openshift-ansible/commit/ead22bb1c3b6d6366502b14b97b7aae5605f8a58 Merge pull request #5518 from ingvagabund/set-quota-backend-bytes-explicitly Automatic merge from submit-queue set the etcd backend quota to 4GB by default Bug: 1492891
Verify this bug with openshift-ansible-3.7.0-0.143.2.git.0.39404c5.el7.noarch.rpm Etcd backend quota was set to 4GB by default now. [root@ip-172-18-9-157 ~]# grep ETCD_QUOTA_BACKEND_BYTES /etc/etcd/etcd.conf ETCD_QUOTA_BACKEND_BYTES=4294967296
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. https://access.redhat.com/errata/RHSA-2017:3188
The needinfo request[s] on this closed bug have been removed as they have been unresolved for 1000 days