In our last post, we talked about how to fix the issue when you can’t start Oracle RAC RCS. Today, let’s talk about how to check the Oracle RAC Listener status.
What is Oracle RAC Listener?
The Oracle Listener is a critical component of the database server and plays an important role within the Oracle architecture. It manages communication between the Oracle database and clients. The listener listens for connection requests on a specific network card port (by default, TCP port 1521) and forwards these connections to the database.
Its main functions include listening for client requests, assigning server processes to client requests, registering instance services, providing failover, and performing load balancing, among others.
How to Check the Oracle RAC Listener Status?
To check the listener status, we generally use the following command:
lsnrctl status
However, this typically only shows the status of the default listener. To check the status of other listeners, use the following commands:
lsnrctl status listener2
lsnrctl status listener_scan1
To check the status of the cluster listener resources, use the following command:
[grid:rac01]:/home/grid> srvctl status listener -n rac01 Listener LISTENER is enabled on node(s) :rac01 Listener LISTENER is running on node(s) :rac01 Listener LISTENER2 is enabled on node(s) :rac01 Listener LISTENER2 is running on node(s) :rac01 [grid:rac01]:/home/grid>
Additionally, regarding the status of listener_scan1: After installing the RAC cluster, there will be two listeners, LISTENER and LISTENER_SCAN1. Both can be used to connect to the database. However, the difference is that without using DNS, the SCAN IP doesn’t fully function as intended. The IP may float to a specific node. Therefore, if you can’t see the status using the lsnrctl status listener_scan1 command on node 1, check node 2.
