-`etcd` will no longer start on data dir created by newer versions (for example etcd v3.6 will not run on v3.7+ data dir). To downgrade data dir please check out `etcdutl migrate` command.
-`etcd` doesn't support serving client requests on the peer listen endpoints (--listen-peer-urls). See [pull/13565](https://github.com/etcd-io/etcd/pull/13565).
- [Decouple raft from etcd](https://github.com/etcd-io/etcd/issues/14713). Migrated raft to a separate [repository](https://github.com/etcd-io/raft), and renamed raft module to `go.etcd.io/raft/v3`.
- Add [`etcd --experimental-enable-lease-checkpoint-persist`](https://github.com/etcd-io/etcd/pull/13508) flag to handle upgrade from v3.5.2 clusters with this feature enabled.
- Add [`etcd --experimental-wait-cluster-ready-timeout`](https://github.com/etcd-io/etcd/pull/13525) flag to wait for cluster to be ready before serving client requests.
- Add [`etcd --max-concurrent-streams`](https://github.com/etcd-io/etcd/pull/14169) flag to configure the max concurrent streams each client can open at a time, and defaults to math.MaxUint32.
- Add [`etcd grpc-proxy --experimental-enable-grpc-logging`](https://github.com/etcd-io/etcd/pull/14266) flag to logging all grpc requests and responses.
- Add [`etcd --experimental-compact-hash-check-enabled --experimental-compact-hash-check-time`](https://github.com/etcd-io/etcd/issues/14039) flags to support enabling reliable corruption detection on compacted revisions.
- Graduated [`--experimental-warning-unary-request-duration` to `--warning-unary-request-duration`](https://github.com/etcd-io/etcd/pull/14414). Note the experimental flag is deprecated and will be decommissioned in v3.7.
- Add [`etcd --experimental-snapshot-catch-up-entries`](https://github.com/etcd-io/etcd/pull/15033) flag to configure number of entries for a slow follower to catch up after compacting the the raft storage entries and defaults to 5k.
- Add [`etcd grpc-proxy start --endpoints-auto-sync-interval`](https://github.com/etcd-io/etcd/pull/14354) flag to enable and configure interval of auto sync of endpoints with server.
- Compile with [Go 1.19+](https://golang.org/doc/devel/release.html#go1.19). Please refer to [gc-guide](https://go.dev/doc/gc-guide) to configure `GOGC` and `GOMEMLIMIT` properly.