**Use case**

Currently, `system.replicas` table has `total_replicas` and `active_replicas` columns which are useful to check/alert when some replicas are down. One problem, these columns are numbers. They tell when there is a problem, but you need to further check ZooKeeper or query all the nodes to detect what exact replicas (hosts) are down/inactive/have problems.

**Describe the solution you'd like**

Add a replicas column maybe as a map which would contain the replica name, and it's status. Or, add 2 array columns with `replica_names` and `active_replica_names`

**Alternative**

Something along the line

```sql
select path, value from system.zookeeper where path IN (
    select concat(path, '/', name) from system.zookeeper where path in (select concat(zookeeper_path, '/replicas') from system.replicas)
)
and name = 'is_active'
```
{
    if (!leader_election)
        return;
    
    
    leader_election->shutdown();
    if (is_leader)
    {
        LOG_INFO(log, "Stopped being leader");
        is_leader = false;
        merge_selecting_task->deactivate();
    }
    
    
    leader_election = nullptr;
}
ConnectionTimeouts StorageReplicatedMergeTree::getFetchPartHTTPTimeouts(ContextPtr local_context)
{
    auto timeouts = ConnectionTimeouts::getHTTPTimeouts(local_context);
    auto settings = getSettings();
    if (settings->replicated_fetches_http_connection_timeout.changed)
        timeouts.connection_timeout = settings->replicated_fetches_http_connection_timeout;
    if (settings->replicated_fetches_http_send_timeout.changed)
        timeouts.send_timeout = settings->replicated_fetches_http_send_timeout;
    if (settings->replicated_fetches_http_receive_timeout.changed)
        timeouts.receive_timeout = settings->replicated_fetches_http_receive_timeout;
    return timeouts;
}
bool StorageReplicatedMergeTree::checkReplicaHavePart(const String & replica, const String & part_name)