Hello,

after updating clickhouse from 21.2.3.15-2 to 21.3.2.5-2 I see those warnings :

 `<Warning> default.osb4_reverse.DirectoryMonitor: Structure does not match (remote: Path LowCardinality(String) ColumnLowCardinality(size = 0, UInt8(size = 0), ColumnUnique(size = 1, String(size = 1))), Value Float64 Float64(size = 0), Time UInt32 UInt32(size = 0), Date Date UInt16(size = 0), Timestamp UInt32 UInt32(size = 0), local: Path LowCardinality(String) ColumnLowCardinality(size = 0, UInt16(size = 0), ColumnUnique(size = 1, String(size = 1))), Value Float64 Float64(size = 0), Time UInt32 UInt32(size = 0), Date Date UInt16(size = 0), Timestamp UInt32 UInt32(size = 0)), implicit conversion will be done`

I think this is related to https://github.com/ClickHouse/ClickHouse/pull/19947

The only difference between remote and local I found inside this log is :

ColumnLowCardinality(size = 0, UInt8(size = 0) to
ColumnLowCardinality(size = 0, UInt16(size = 0)

But I don't see the difference between the tables.

```
SHOW CREATE TABLE default.osb4_reverse

CREATE TABLE default.osb4_reverse
(
    `Path` LowCardinality(String) CODEC(ZSTD(15)),
    `Value` Float64 CODEC(Gorilla, ZSTD(22)),
    `Time` UInt32 CODEC(DoubleDelta, ZSTD(15)),
    `Date` Date CODEC(Delta(2), ZSTD(22)),
    `Timestamp` UInt32 CODEC(ZSTD(15))
)
ENGINE = Distributed('osb4_hpc_metrics', '', 'osb4_reverse', rand())


CREATE TABLE osb4_metrics_r0.osb4_reverse
(
    `Path` LowCardinality(String) CODEC(ZSTD(15)),
    `Value` Float64 CODEC(Gorilla, ZSTD(22)),
    `Time` UInt32 CODEC(DoubleDelta, ZSTD(15)),
    `Date` Date CODEC(Delta(2), ZSTD(22)),
    `Timestamp` UInt32 CODEC(ZSTD(15))
)
ENGINE = ReplicatedReplacingMergeTree('/clickhouse/clusters/osb4_hpc_metrics/tables/{table4}/data', '{host2}')
PARTITION BY toYYYYMM(Date)
ORDER BY (Path, Time)
TTL Date + toIntervalMonth(6)
SETTINGS index_granularity = 8192
```

Any hints ?

Ralph
{
    const auto pool_factory = [&storage, &name] (const Cluster::Address & address) -> ConnectionPoolPtr
    {
        const auto & cluster = storage.getCluster();
        const auto & shards_info = cluster->getShardsInfo();
        const auto & shards_addresses = cluster->getShardsAddresses();
        
        
        if (address.shard_index != 0)
        {
            if (!address.replica_index)
                throw Exception(ErrorCodes::INCORRECT_FILE_NAME,
                    "Wrong replica_index ({})", address.replica_index, name);
            if (address.shard_index > shards_info.size())
                throw Exception(ErrorCodes::INCORRECT_FILE_NAME,
                    "No shard with shard_index={} ({})", address.shard_index, name);
            const auto & shard_info = shards_info[address.shard_index - 1];
            if (address.replica_index > shard_info.per_replica_pools.size())
                throw Exception(ErrorCodes::INCORRECT_FILE_NAME,
                    "No shard with replica_index={} ({})", address.replica_index, name);
            return shard_info.per_replica_pools[address.replica_index - 1];
        }
        
        for (size_t shard_index = 0; shard_index < shards_info.size(); ++shard_index)
        {
            const Cluster::Addresses & replicas_addresses = shards_addresses[shard_index];
            for (size_t replica_index = 0; replica_index < replicas_addresses.size(); ++replica_index)
            {