`2021.12.12 04:24:12.020896 [ 491 ] {} <Information> RaftInstance: parameters: timeout 0 - 0, heartbeat 0, leadership expiry 0, max batch 100, backoff 50, snapshot distance 10000, log sync stop gap 99999, reserved logs -1530494976, client timeout 
10000, auto forwarding ON, API call type ASYNC, custom commit quorum size 0, custom election quorum size 0, snapshot receiver INCLUDED, leadership transfer wait time 0, grace period of lagging state machine 0, snapshot IO: BLOCKING`

Why `reserved logs -1530494976` (negative number)?
`timeout 0 - 0` - not obvious what does it mean.
`snapshot receiver INCLUDED` - it is screaming for what?
{
    auto srv_config = state_manager->get_srv_config();
    return srv_config->is_learner();
}
bool KeeperServer::isFollower() const
{
    return !isLeader() && !isObserver();
}
bool KeeperServer::isLeaderAlive() const
{
    return raft_instance->is_leader_alive();
}
uint64_t KeeperServer::getFollowerCount() const
{
    return raft_instance->get_peer_info_all().size();
}
uint64_t KeeperServer::getSyncedFollowerCount() const
{
    uint64_t last_log_idx = raft_instance->get_last_log_idx();
    const auto followers = raft_instance->get_peer_info_all();
    uint64_t stale_followers = 0;
    const uint64_t stale_follower_gap = raft_instance->get_current_params().stale_log_gap_;
    for (const auto & fl : followers)
    {
        if (last_log_idx > fl.last_log_idx_ + stale_follower_gap)
            stale_followers++;
    }
    return followers.size() - stale_followers;
}
nuraft::cb_func::ReturnCode KeeperServer::callbackFunc(nuraft::cb_func::Type type, nuraft::cb_func::Param * param)