A Tarantool EE cluster CAN host its own etcd config store (every node runs app.roles.etcd, KV replicated under Raft) and migrate file->etcd live by rolling restart — VERIFIED end-to-end on EE 3.7.0 in examples/tarantool-ee-self-hosted-etcd. Hard rules learned: (1) cannot cold-boot (config.etcd fetches before box.cfg/role-start; all-down = nobody serves etcd = deadlock) — retain local cluster-config.yaml as cold-boot seed; (2) the EE config.etcd source pins to Endpoints[0] and does NOT fail over on 'no leader' (same as clientv3 pick-first) — so TT_CONFIG_ETCD_ENDPOINTS MUST list the current Raft leader FIRST or boot dies on a follower; the boot fetch is NOT a plain Range so read_pref=any doesn't save it; (3) migrate the Raft leader LAST and wait for a stable single-leader between rolling steps. read_pref=any still set as defense for plain Range reads.