Querying Status

Background

openGauss allows you to query the entire status. You can check whether the openGauss or a single host is running properly based on the query result.

Prerequisites

openGauss has started.

Procedure

Log in as the OS user omm to the primary node of the database.
Run the following command to query openGauss status.
```
gs_om -t status --detail
```
Table 1 describes parameters in the query result.
To query the instance state on a host, add -h to the command. The following is an example:
```
gs_om -t status -h plat2 
```
plat2 indicates the name of the host to be queried.

Parameter Description

Table 1 Node role description

Column	Description	Column Value
cluster_state	openGauss status, which indicates whether the entire openGauss is running properly.	Normal: openGauss is available and the data has redundancy backup. All the processes are running and the primary-standby relationship is normal. Unavailable: openGauss is unavailable. Degraded: openGauss is available and faulty database nodes and primary database nodes exist.
node	Host name	Name of the host where the instance is located. If there are multiple AZs, the AZ ID of the host will be displayed.
node_ip	Host IP address	Specifies the IP address of a host where an instance is located.
instance	Instance ID	Specifies the instance ID.
state	Instance role	Normal: The instance a single host instance. Primary: The instance is a primary instance. Standby: The instance is the standby. Cascade Standby: The instance is a cascaded standby instance. Pending: The instance is in the quorum phase. Unknown: The instance state is unknown. Down: The instance is down. Abnormal: The node is abnormal. Manually stopped: The node has been manually stopped.

Each role has different states, such as startup and connection. The states are described as follows:

Table 2 Node states

State	Description
Normal	The node starts up normally.
Need repair	The node needs to be restored.
Starting	The node is starting up.
Wait promoting	The node is waiting for upgrade. For example, after the standby node sends an upgrade request to the primary node, the standby node is waiting for the response from the primary node.
Promoting	The standby node is being upgraded to the primary node.
Demoting	The node is being downgraded, for example, the primary node is being downgraded to the standby node.
Building	The standby node fails to be started and needs to be rebuilt.
Catchup	The standby node is catching up with the primary node.
Coredump	The node program breaks down.
Unknown	The node state is unknown.

If a node is in Need repair state, you need to rebuild the node to restore it. Generally, the reasons for rebuilding a node are as follows:

Table 3 Node rebuilding causes

State	Description
Normal	The node starts up normally.
WAL segment removed	WALs of the primary node do not exist, and logs of the standby node are later than those of the primary node.
Disconnect	The standby node cannot be connected to the primary node.
Version not matched	The binary versions of the primary and standby nodes are inconsistent.
Mode not matched	Nodes do not match the primary and standby roles. For example, two standby nodes are connected.
System id not matched	The database system IDs of the primary and standby nodes are inconsistent. The system IDs of the primary and standby nodes must be the same.
Timeline not matched	The log timelines are inconsistent.
Unknown	Other causes.

Examples

View openGauss status details, including instance states.

gs_om -t status --detail 
[   Cluster State   ] 
 
cluster_state   : Normal 
redistributing  : No 
current_az      : AZ_ALL 
 
[  Datanode State   ] 
node                           node_ip           port                           instance                                   state 
---------------------------------------------------------------------------------------------------------------- 
1  pekpopgsci00235  10.244.62.204    5432      6001 /opt/gaussdb/cluster/data/dn1   P Primary Normal 
2  pekpopgsci00238  10.244.61.81      5432      6002 /opt/gaussdb/cluster/data/dn1   S Standby Normal