fix: reset follower with stale state before add-node to prevent "Node is not empty" loop#1734
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svils wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
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fix: reset follower with stale state before add-node to prevent "Node is not empty" loop#1734svils wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
svils wants to merge 1 commit intoOT-CONTAINER-KIT:mainfrom
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… is not empty" loop ExecuteRedisReplicationCommand uses `redis-cli --cluster add-node` to join followers to the cluster. This command requires the target node to be completely empty — no cluster state and no keys in database 0. After a leader-only CLUSTER RESET during single-node bootstrap (via executeFailoverCommand), the follower retains its previous cluster state and replicated data. The operator then enters an infinite error loop: [ERR] Node <cluster>-follower-0...is not empty. Either the node already knows other nodes (check with CLUSTER NODES) or contains some key in database 0. Add resetFollowerIfNotEmpty: before running add-node, check whether the follower knows other nodes or has keys in db0. If so, issue CLUSTER RESET HARD to clear both cluster state and data so add-node can succeed. The follower will re-sync from the master via full sync after joining. Related: OT-CONTAINER-KIT#1407 Signed-off-by: svils <63684363+svils@users.noreply.github.com>
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iamabhishek-dubey and
shubham-cmyk
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Summary
redis-cli --cluster add-node, check if the follower has stale cluster state (knows other nodes) or data in db0CLUSTER RESET HARDto clear both, allowingadd-nodeto succeedAfter a leader-only
CLUSTER RESETduring single-node bootstrap, the follower retains its previous cluster state and replicated data.add-noderejects it with "Node is not empty", causing an infinite error loop on every reconcile cycle.Fixes #1733
Related: #1407
Test plan
resetFollowerIfNotEmptycovering: empty node (no-op), stale cluster state, keys in db0, error pathsk8sutilstest suite passesclusterSize: 1with 1 follower) — delete the leader PVC to trigger bootstrap, confirm follower is reset and re-added automatically