SHOW REPLICA STATUS
Syntax
SHOW SLAVE ["connection_name"] STATUS [FOR CHANNEL "connection_name"] SHOW REPLICA ["connection_name"] STATUS [FOR CHANNEL "connection_name"] -- From MariaDB 10.5.1
or
SHOW ALL SLAVES STATUS SHOW ALL REPLICAS STATUS -- From MariaDB 10.5.1
Description
This statement is to be run on a replica and provides status information on essential parameters of the replica threads.
This statement requires the SUPER privilege, the REPLICATION_CLIENT privilege, or, from MariaDB 10.5.2, the REPLICATION SLAVE ADMIN privilege, or, from MariaDB 10.5.9, the REPLICA MONITOR privilege.
Multi-Source
The ALL and "connection_name" options allow you to connect to many primaries at the same time.
ALL SLAVES (or ALL REPLICAS from MariaDB 10.5.1) gives you a list of all connections to the primary nodes.
The rows will be sorted according to Connection_name.
If you specify a connection_name, you only get the information about that
connection. If connection_name is not used, then the name set by default_master_connection is used. If the connection name doesn't exist you will get an error:
There is no master connection for 'xxx'.
MariaDB starting with 10.7.0
The FOR CHANNEL keyword was added for MySQL compatibility. This is identical to
using the channel_name directly after SHOW SLAVE.
Column Descriptions
The order in which the columns appear depends on the MariaDB version. This means that extracting a column value is best done by comparing the field name instead of using a fixed offset into the row.
MariaDB starting with 11.6.0
These columns can also be viewed/extracted from the INFORMATION_SCHEMA.SLAVE_STATUS table
| Name | Description |
|---|---|
| Connection_name | Name of the primary connection. Returned with SHOW ALL SLAVES STATUS (or SHOW ALL REPLICAS STATUS from MariaDB 10.5.1) only. |
| Slave_SQL_State | State of SQL thread. Returned with SHOW ALL SLAVES STATUS (or SHOW ALL REPLICAS STATUS from MariaDB 10.5.1) only. See Slave SQL Thread States. |
| Slave_IO_State | State of I/O thread. See Slave I/O Thread States. |
| Master_host | Master host that the replica is connected to. |
| Master_user | Account user name being used to connect to the primary. |
| Master_port | The port being used to connect to the primary. |
| Connect_Retry | Time in seconds between retries to connect. The default is 60. The CHANGE MASTER TO statement can set this. The master-retry-count option determines the maximum number of reconnection attempts. |
| Master_Log_File | Name of the primary binary log file that the I/O thread is currently reading from. |
| Read_Master_Log_Pos | Position up to which the I/O thread has read in the current primary binary log file. |
| Relay_Log_File | Name of the relay log file that the SQL thread is currently processing. |
| Relay_Log_Pos | Position up to which the SQL thread has finished processing in the current relay log file. |
| Relay_Master_Log_File | Name of the primary binary log file that contains the most recent event executed by the SQL thread. |
| Slave_IO_Running | Whether the replica I/O thread is running and connected (Yes), running but not connected to a primary (Connecting) or not running (No). |
| Slave_SQL_Running | Whether or not the SQL thread is running. |
| Replicate_Rewrite_DB | Databases specified for replicating and rewriting with the replicate_rewrite_db option. Added in MariaDB 10.11 |
| Replicate_Do_DB | Databases specified for replicating with the replicate_do_db option. |
| Replicate_Ignore_DB | Databases specified for ignoring with the replicate_ignore_db option. |
| Replicate_Do_Table | Tables specified for replicating with the replicate_do_table option. |
| Replicate_Ignore_Table | Tables specified for ignoring with the replicate_ignore_table option. |
| Replicate_Wild_Do_Table | Tables specified for replicating with the replicate_wild_do_table option. |
| Replicate_Wild_Ignore_Table | Tables specified for ignoring with the replicate_wild_ignore_table option. |
| Last_Errno | Alias for Last_SQL_Errno (see below) |
| Last Error | Alias for Last_SQL_Error (see below) |
| Skip_Counter | Number of events that a replica skips from the master, as recorded in the sql_slave_skip_counter system variable. |
| Exec_Master_Log_Pos | Position up to which the SQL thread has processed in the current master binary log file. Can be used to start a new replica from a current replica with the CHANGE MASTER TO ... MASTER_LOG_POS option. |
| Relay_Log_Space | Total size of all relay log files combined. |
| Until_Condition | One of four possible values: None, Master, Relay, or Gtid, depending on the respective START SLAVE UNTIL condition. |
| Until_Log_File | The MASTER_LOG_FILE value of the START SLAVE UNTIL condition. |
| Until_Log_Pos | The MASTER_LOG_POS value of the START SLAVE UNTIL condition. |
| Master_SSL_Allowed | Whether an SSL connection is permitted (Yes), not permitted (No) or permitted but without the replica having SSL support enabled (Ignored) |
| Master_SSL_CA_File | The MASTER_SSL_CA option of the CHANGE MASTER TO statement. |
| Master_SSL_CA_Path | The MASTER_SSL_CAPATH option of the CHANGE MASTER TO statement. |
| Master_SSL_Cert | The MASTER_SSL_CERT option of the CHANGE MASTER TO statement. |
| Master_SSL_Cipher | The MASTER_SSL_CIPHER option of the CHANGE MASTER TO statement. |
| Master_SSL_Key | The MASTER_SSL_KEY option of the CHANGE MASTER TO statement. |
| Seconds_Behind_Master | Difference between the timestamp logged on the master for the event that the replica is currently processing, and the current timestamp on the replica. Zero if the replica is not currently processing an event. With serial replication, seconds_behind_master is updated when the SQL thread begins executing a transaction. With parallel replication, seconds_behind_master is updated only after transactions commit. Starting in MariaDB 10.3.38, 10.4.28, 10.5.19, 10.6.12, 10.8.7, 10.9.5, 10.10.3, and 10.11.2, an exception is drawn on the parallel replica to additionally update seconds_behind_master when the first transaction received after idling is queued to a worker for execution, to provide a reliable initial value for the duration until a transaction commits. Additional behaviors to be aware of are as follows: 1) Seconds_Behind_Master will update for ignored events, e.g. those skipped due to sql_slave_skip_counter. 2) On the serial replica, transactions with prior timestamps can update Seconds_Behind_Master such that it can go backwards, though this is not true for the parallel replica. 3) When configured with MASTER_DELAY, as a replicated transaction begins executing (i.e. on a serial or post-idle parallel replica), Seconds_Behind_Master will update before delaying, and while delaying occurs will grow to encompass the configured value. 4) There is a known issue, tracked by MDEV-17516, such that Seconds_Behind_Master will initially present as 0 on replica restart until a replicated transaction begins executing, even if the last replica session was lagging behind when stopped. |
| Master_SSL_Verify_Server_Cert | The MASTER_SSL_VERIFY_SERVER_CERT option of the CHANGE MASTER TO statement. |
| Last_IO_Errno | Error code of the most recent error that caused the I/O thread to stop (also recorded in the replica's error log). 0 means no error. RESET SLAVE or RESET MASTER will reset this value. |
| Last_IO_Error | Error message of the most recent error that caused the I/O thread to stop (also recorded in the replica's error log). An empty string means no error. RESET SLAVE or RESET MASTER will reset this value. |
| Last_SQL_Errno | Error code of the most recent error that caused the SQL thread to stop (also recorded in the replica's error log). 0 means no error. RESET SLAVE or RESET MASTER will reset this value. |
| Last_SQL_Error | Error message of the most recent error that caused the SQL thread to stop (also recorded in the replica's error log). An empty string means no error. RESET SLAVE or RESET MASTER will reset this value. |
| Replicate_Ignore_Server_Ids | List of server_ids that are currently being ignored for replication purposes, or an empty string for none, as specified in the IGNORE_SERVER_IDS option of the CHANGE MASTER TO statement. |
| Master_Server_Id | The master's server_id value. |
| Master_SSL_Crl | The MASTER_SSL_CRL option of the CHANGE MASTER TO statement. |
| Master_SSL_Crlpath | The MASTER_SSL_CRLPATH option of the CHANGE MASTER TO statement. |
| Using_Gtid | Whether or not global transaction ID's are being used for replication (can be No, Slave_Pos, or Current_Pos). |
| Gtid_IO_Pos | Current global transaction ID value. |
| Retried_transactions | Number of retried transactions for this connection. Returned with SHOW ALL SLAVES STATUS only. |
| Max_relay_log_size | Max relay log size for this connection. Returned with SHOW ALL SLAVES STATUS only. |
| Executed_log_entries | How many log entries the replica has executed. Returned with SHOW ALL SLAVES STATUS only. |
| Slave_received_heartbeats | How many heartbeats we have got from the master. Returned with SHOW ALL SLAVES STATUS only. |
| Slave_heartbeat_period | How often to request a heartbeat packet from the master (in seconds). Returned with SHOW ALL SLAVES STATUS only. |
| Gtid_Slave_Pos | GTID of the last event group replicated on a replica server, for each replication domain, as stored in the gtid_slave_pos system variable. Returned with SHOW ALL SLAVES STATUS only. |
| SQL_Delay | Value specified by MASTER_DELAY in CHANGE MASTER (or 0 if none). |
| SQL_Remaining_Delay | When the replica is delaying the execution of an event due to MASTER_DELAY, this is the number of seconds of delay remaining before the event will be applied. Otherwise, the value is NULL. |
| Slave_SQL_Running_State | The state of the SQL driver threads, same as in SHOW PROCESSLIST. When the replica is delaying the execution of an event due to MASTER_DELAY, this field displays: "Waiting until MASTER_DELAY seconds after master executed event". |
| Slave_DDL_Groups | This status variable counts the occurrence of DDL statements. This is a replica-side counter for optimistic parallel replication. |
| Slave_Non_Transactional_Groups | This status variable counts the occurrence of non-transactional event groups. This is a replica-side counter for optimistic parallel replication. |
| Slave_Transactional_Groups | This status variable counts the occurrence of transactional event groups. This is a replica-side counter for optimistic parallel replication. |
| Replicate_Rewrite_DB | Value of configured replicate_rewrite_db system variable/option. |
| Retried_transactions | The number of times that replicating transactions have been retried due to temporary errors (e.g. deadlocks in parallel replication). |
| Max_relay_log_size | Maximum size of the relay log (configured by variable max_relay_log_size). |
| Executed_log_entries | Number of binary log events that have been executed, irrespective of error outcome (i.e. if the event execution results in an error, this number will still increase). |
| Slave_received_heartbeats | Number of Heartbeat Log Events that the slave has received. Note this counter does not reset when the slave is restarted; only when a new CHANGE MASTER command has executed. |
| Slave_heartbeat_period | Configured (by CHANGE MASTER TO MASTER_HEARTBEAT_PERIOD) interval in seconds between replication heartbeats. |
| Gtid_Slave_Pos | The value of the global variable gtid_slave_pos, i.e. the GTID of the last transaction applied to the database by the server's replica threads for each replication domain. |
| Master_last_event_time | Timestamp of the last event read from the primary by the IO thread. NULL until the replica has started and the replica has read one query event from the primary that changes data. From MariaDB 11.6. |
| Slave_last_event_time | Primary timestamp of the last event committed on the replica. NULL until the replica has started and the replica has read one query event from the primary that changes data. From MariaDB 11.6. |
| Master_Slave_time_diff | The difference of the above two timestamps. NULL until the replica has started and the replica has read one query event from the primary that changes data. From MariaDB 11.6. |
Examples
If you issue this statement using the mariadb client,
you can use a \G
SHOW SLAVE STATUS\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: db01.example.com
Master_User: replicant
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mariadb-bin.000021
Read_Master_Log_Pos: 17315
Relay_Log_File: relay-bin.000042
Relay_Log_Pos: 17446
Relay_Master_Log_File: mariadb-bin.000021
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 17146
Relay_Log_Space: 17972
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: Yes
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 6
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_SSL_Crl:
Master_SSL_Crlpath:
Using_Gtid: Slave_Pos
Gtid_IO_Pos: 0-1-2042
Replicate_Do_Domain_Ids:
Replicate_Ignore_Domain_Ids:
Parallel_Mode: optimistic
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Updating
Slave_DDL_Groups: 1
Slave_Non_Transactional_Groups: 0
Slave_Transactional_Groups: 2041
Replicate_Rewrite_DB:
SHOW ALL SLAVES STATUS\G
*************************** 1. row ***************************
Connection_name:
Slave_SQL_State: Updating
Slave_IO_State: Waiting for master to send event
Master_Host: db01.example.com
Master_User: replicant
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mariadb-bin.000021
Read_Master_Log_Pos: 17315
Relay_Log_File: relay-bin.000042
Relay_Log_Pos: 17446
Relay_Master_Log_File: mariadb-bin.000021
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 17146
Relay_Log_Space: 17972
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: Yes
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 6
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_SSL_Crl:
Master_SSL_Crlpath:
Using_Gtid: Slave_Pos
Gtid_IO_Pos: 0-1-2042
Replicate_Do_Domain_Ids:
Replicate_Ignore_Domain_Ids:
Parallel_Mode: optimistic
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Updating
Slave_DDL_Groups: 1
Slave_Non_Transactional_Groups: 0
Slave_Transactional_Groups: 2041
Replicate_Rewrite_DB:
Retried_transactions: 0
Max_relay_log_size: 1073741824
Executed_log_entries: 6330
Slave_received_heartbeats: 0
Slave_heartbeat_period: 60.000
Gtid_Slave_Pos: 0-1-2041
Master_last_event_time: 2024-12-12 06:53:52
Slave_last_event_time: 2024-12-12 06:53:50
Master_Slave_time_diff: 2
You can also access some of the variables directly from status variables:
SET @@default_master_connection="test" ; show status like "%slave%" Variable_name Value Com_show_slave_hosts 0 Com_show_slave_status 0 Com_start_all_slaves 0 Com_start_slave 0 Com_stop_all_slaves 0 Com_stop_slave 0 Rpl_semi_sync_slave_status OFF Slave_connections 0 Slave_heartbeat_period 1800.000 Slave_open_temp_tables 0 Slave_received_heartbeats 0 Slave_retried_transactions 0 Slave_running OFF Slaves_connected 0 Slaves_running 1
See Also
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