cdc exit with error: etcdserver: mvcc: required revision has been compacted

What did you do?

1. inject network partition between pd and cdc for a while

What did you expect to see?

cdc works normally

What did you see instead?

one cdc node exited with error:
[2025/11/04 15:06:16.702 +08:00] [WARN] [server.go:131] ["cdc server exits with error"] [error="etcdserver: mvcc: required revision has been compacted"] errorVerbose="etcdserver: mvcc: required revision has been compacted[ngithub.com/pingcap/errors.Trace\n\tgithub.com/pingcap/errors@v0.11.5-0.20250523034308-74f78ae071ee/juju_adaptor.go:15\ngithub.com/pingcap/ticdc/pkg/orchestrator.(*EtcdWorker).Run\n\tgithub.com/pingcap/ticdc/pkg/orchestrator/etcd_worker.go:195\ngithub.com/pingcap/ticdc/server/watcher.(*EtcdWatcher).RunEtcdWorker\n\tgithub.com/pingcap/ticdc/server/watcher/etcd_watcher.go:61\ngithub.com/pingcap/ticdc/server/watcher.(*NodeManager).Run\n\tgithub.com/pingcap/ticdc/server/watcher/module_node_manager.go:169\ngithub.com/pingcap/ticdc/server.(*server).Run.(*server).Run.func2.func7\n\tgithub.com/pingcap/ticdc/server/server.go:317\ngolang.org/x/sync/errgroup.(*Group).Go.func1\n\tgolang.org/x/sync@v0.17.0/errgroup/errgroup.go:93\nruntime.goexit\n\truntime/asm_amd64.s:1700

Versions of the cluster

Upstream TiDB cluster version (execute SELECT tidb_version(); in a MySQL client):

(paste TiDB cluster version here)

Upstream TiKV version (execute tikv-server --version):

(paste TiKV version here)

TiCDC version (execute cdc version):

(paste TiCDC version here)

Start with the network-partition scenario and trace the failure at pkg/orchestrator/etcd_worker.go:195 through server/watcher/etcd_watcher.go and server/watcher/module_node_manager.go. Reproduce the compacted-revision error if possible, then establish the expected recovery behavior for the CDC node and add coverage for that behavior. The missing cluster and TiCDC versions should be collected before implementation.