YugabyteDB Anywhere supports monitoring YSQL replication slots used by CDC with the [PostgreSQL replication protocol](../../../additional-features/change-data-capture/using-logical-replication/). A replication slot is a PostgreSQL feature which ensures that a stream of changes stored in a WAL log file is replicated to the destination in the correct order.

You can view all the replications that are present in a universe along with the following service metrics associated with each CDC replication slot:

- Current lag
- Time to expire
- Messages emitted
- Bytes emitted

The following table describes the CDC service metrics available.

| Metric Name | Details |
| :---------- | :------ |
| cdcsdk_sent_lag_micros | Current lag. Lag between the last committed record in the producer and last sent record. |
| cdcsdk_expiry_time_ms | Time to expire. Remaining expiry time of CDC replication slot in milliseconds. |
| cdcsdk_change_event_count | Messages emitted. The change event count metric shows the number of records sent by the CDC service.|
| cdcsdk_traffic_sent | Bytes emitted. Total traffic sent in bytes from the CDC replication slot. |

For more information on CDC metrics, refer to [Monitor CDC](../../../additional-features/change-data-capture/using-logical-replication/monitor/).

To view your universe's replication slots, navigate to your universe and select the **CDC Replication Slots** tab.

![Replication slots](/images/yp/alerts-monitoring/cdc/replication-slots1.png)

**CDC Replication Slots** lists all replications, database names, and the slot status. You can also view detailed metrics by selecting a replication slot in the list.

![Replication slot row](/images/yp/alerts-monitoring/cdc/replication-slots2.png)

## Limitation

- Currently, YugabyteDB supports CDC replication slots only for YSQL databases.

## Learn more

- [CDC using PostgreSQL replication protocol](../../../additional-features/change-data-capture/using-logical-replication/)