**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 (entry.type == LogEntry::ATTACH_PART)
    {
        if (MutableDataPartPtr part = attachPartHelperFoundValidPart(entry); part)
        {
            LOG_TRACE(log, "Found valid local part for {}, preparing the transaction", part->name);
            Transaction transaction(*this);
            renameTempPartAndReplace(part, nullptr, &transaction);
            checkPartChecksumsAndCommit(transaction, part);
            writePartLog(PartLogElement::Type::NEW_PART, {}, 0 ,
                part->name, part, {} , nullptr);
            return true;
        }
        LOG_TRACE(log, "Didn't find valid local part for {} ({}), will fetch it from other replica",
            entry.new_part_name,
            entry.actual_new_part_name);
    }
    if (is_get_or_attach && entry.source_replica == replica_name)
        LOG_WARNING(log, "Part {} from own log doesn't exist.", entry.new_part_name);
    
    
    if (entry.quorum && getZooKeeper()->exists(fs::path(zookeeper_path) / "quorum" / "failed_parts" / entry.new_part_name))
    {
        LOG_DEBUG(log, "Skipping action for part {} because quorum for that part was failed.", entry.new_part_name);
        return true;    
    }
    bool do_fetch = false;
    switch (entry.type)
    {
        case LogEntry::ATTACH_PART: