Maintenance Command Status

After executing maintenance operations, you can monitor the outcomes of these operations, along with the current health status of the database, through a series of commonly used command combinations. By sequentially running the showopstatus and showtablestatus commands, you can ultimately verify the successful completion of the relevant maintenance tasks.

Step 1: View Command Status with showopstatus

The showopstatus command serves the purpose of observing the execution status of specific maintenance commands. The current NS client supports this command to track the status of maintenance commands like addreplica, delreplica, migrate, offlineendpoint, recoverendpoint, changeleader, and recovertable. For a comprehensive understanding of these supported maintenance commands, refer to the Operations CLI document.

You can monitor the status of relevant commands by utilizing the showopstatus command of the OpenMLDB Operations Tool openmldb_ops.py, as shown in the example below:

python tools/openmldb_ops.py --openmldb_bin_path=./bin/openmldb --zk_cluster=127.0.0.1:2181 --zk_root_path=/openmldb --cmd=showopstatus

Due to the asynchronous nature of maintenance command execution, you might need to run the showopstatus command multiple times to confirm the final state. The state transitions for related commands can occur in three stages:

1. kInited => kDoing => kDone: Indicates successful command execution.

2. kInited => kDoing => kFailed: Denotes a failed command execution.

3. kInited => kCancelled: This state may arise after manually executing the cancelop command.

Once the command running status changes to kDone, it signifies the successful execution of relevant commands. You can then proceed to the subsequent steps and use the showtablestatus command to inspect the status of tables.

Step 2: View Table Status with showtablestatus

After successfully executing the relevant maintenance commands, it’s crucial to perform an additional verification to identify any anomalies in the table status. This verification can be conducted using the showtablestatus command within the OpenMLDB Operations and Maintenance Tool. For instance:

python tools/openmldb_ops.py --openmldb_bin_path=./bin/openmldb --zk_cluster=127.0.0.1:2181 --zk_root_path=/openmldb --cmd=showtablestatus

Upon execution, this command will generate a series of table-related information. Of particular importance is the column labeled Partition_unalive. If this column’s value is 0, it signifies that the table is in a normal state. Conversely, any non-zero value indicates the presence of an anomaly, as illustrated in the following example: