Purpose
You can use this statement to maintain the status of OBServer nodes in the system and control the add, delete, start, and stop operations of the OBServer nodes.
You can execute this statement only in the sys tenant.
Syntax
alter_system_server_stmt:
ALTER SYSTEM server_action SERVER ip_port_list [zone];
server_action:
ADD
| DELETE
| CANCEL DELETE
| START
| STOP
| FORCE STOP
| ISOLATE
ip_port_list:
ip_port [, ip_port ...]
Parameters
| Parameter | Description |
|---|---|
| ip_port | The IP address and port number of the OBServer node. |
| zone | If a zone is specified, zone verification is performed for the OBServer node to be maintained. |
| ADD | Adds an OBServer node. ADD adds an OBServer node to the service list. Only OBServer nodes in the service list can provide services. |
| DELETE | Deletes an OBServer node. DELETE deletes an OBServer node from the service list only after the OBServer node is cleared. This statement can cause unit migration. |
| CANCEL DELETE | Cancels the deletion of an OBServer node. |
| START | Starts an OBServer node. |
| STOP | Stops an OBServer node. STOP checks if the majority of replicas are still available after an OBServer node is stopped, and waits until the clogs are synchronized and the leader replica is moved to another node (namely, leader re-election). |
| FORCE STOP | Force stops an OBServer node. FORCE STOP checks if the majority of replicas are still available after an OBServer node is stopped, and waits until the leader replica is moved to another node (namely, leader re-election).
NoticeForce stopping an OBServer node is not a common O&M operation. This operation is not secure as it does not wait until the clogs are synchronized. It is not recommended. |
| ISOLATE | Isolates the failed OBServer node, so that new read/write requests are not routed to the isolated failed node. ISOLATE does not wait until the leader replica is switched to another node (namely, leader re-election). |
Examples
Add the OBServer node xxx.xx.xxx.xx1 to a cluster.
obclient> ALTER SYSTEM ADD SERVER 'xxx.xx.xxx.xx1:xxxx' ZONE 'zone1';