Proof using.
unfold raft_net_invariant_do_generic_server, nextIndex_safety.
simpl.
intros.
repeat find_higher_order_rewrite.
update_destruct_simplify.
- eauto using nextIndex_safety_preserved, doGenericServer_nextIndex_preserved.
- auto.
Qed.

Lemma nextIndex_safety_state_same_packet_subset :
raft_net_invariant_state_same_packet_subset nextIndex_safety.