**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'
```
zkutil::ZooKeeper & zookeeper, String & partition_id, LogEntry & entry, ContextPtr query_context, bool detach)
{
    String alter_partition_version_path = zookeeper_path + "/alter_partition_version";
    Coordination::Stat alter_partition_version_stat;
    zookeeper.get(alter_partition_version_path, &alter_partition_version_stat);
    MergeTreePartInfo drop_range_info;
    
    std::optional<EphemeralLockInZooKeeper> delimiting_block_lock;
    if (!getFakePartCoveringAllPartsInPartition(partition_id, drop_range_info, delimiting_block_lock))
    {
        LOG_INFO(log, "Will not drop partition {}, it is empty.", partition_id);
        return false;
    }
    clearBlocksInPartition(zookeeper, partition_id, drop_range_info.min_block, drop_range_info.max_block);
    String drop_range_fake_part_name = getPartNamePossiblyFake(format_version, drop_range_info);
    LOG_DEBUG(log, "Disabled merges covered by range {}", drop_range_fake_part_name);
    
    entry.type = LogEntry::DROP_RANGE;
    entry.source_replica = replica_name;
    entry.new_part_name = drop_range_fake_part_name;