raft: correct comments

src/v/raft/consensus.cc

@@ -1829,15 +1829,15 @@ ss::future<vote_reply> consensus::do_vote(vote_request r) {
         _term = r.term;
         _voted_for = {};
         term_changed = true;
-        do_step_down("voter_term_greater");
+        do_step_down("candidate_term_greater");
         if (_leader_id) {
             _leader_id = std::nullopt;
             trigger_leadership_notification();
         }
 
         // do not grant vote if log isn't ok
         if (!reply.log_ok) {
-            // even tough we step down we do not want to update the hbeat as it
+            // even though we step down we do not want to update the hbeat as it
             // would cause subsequent votes to fail (_hbeat is updated by the
             // leader)
             _hbeat = clock_type::time_point::min();

src/v/raft/consensus.h

@@ -825,7 +825,7 @@ class consensus {
     bool _transferring_leadership{false};
 
     /// useful for when we are not the leader
-    clock_type::time_point _hbeat = clock_type::now();
+    clock_type::time_point _hbeat = clock_type::now(); // is max() iff leader
     clock_type::time_point _became_leader_at = clock_type::now();
     clock_type::time_point _instantiated_at = clock_type::now();
 

src/v/raft/vote_stm.cc

@@ -342,7 +342,7 @@ ss::future<> vote_stm::wait_for_next_reply() {
 ss::future<> vote_stm::wait() { return _vote_bg.close(); }
 
 ss::future<> vote_stm::update_vote_state(ssx::semaphore_units u) {
-    // use reply term to update voter term
+    // use reply term to update our term
     for (auto& [_, r] : _replies) {
         if (r.value && r.value->has_value()) {
             auto term = r.value->value().term;
@@ -420,7 +420,7 @@ ss::future<> vote_stm::update_vote_state(ssx::semaphore_units u) {
 
     auto ec = co_await replicate_config_as_new_leader(std::move(u));
 
-    // if we didn't replicated configuration, step down
+    // even if failed to replicate, don't step down: followers may be behind
     if (ec) {
         vlog(
           _ctxlog.info,