OEM 13c & 24ai ASM Instances Targets Showing Down in OEM Console

 In Oracle Enterprise Manager (OEM) Cloud Control, ASM instances targets are shown as DOWN in OEM console, and Cluster ASM are shown as "Availability Evaluation Error".

Test Connection on Monitoring Configuration page is successful with both Cluster ASM and all ASM instances.

Cluster ASM and all ASM instances are accessible on their home page after successful logging in with SYS user.

SQL Plus can remotely connect to ASM instances with following connection strings,

connect asmsnmp/pasword@host01-vip/+ASM/+ASM1 as sysdba

connect asmsnmp/pasword@host02-vip/+ASM/+ASM2 as sysdba

SQL> connect asmsnmp/password@host01-vip/+ASM/+ASM1 as sysdba
Connected. 
SQL> connect asmsnmp/password@host02-vip/+ASM/+ASM2 as sysdba
Connected.

Following command succeeded,

<AGENT_HOME>/bin/emctl control agent runCollection "<target>":osm_instance Response

[oracle@host01]$ emctl control agent runCollection "+ASM1_host01":osm_instance Response
Oracle Enterprise Manager 24ai Release 1
Copyright (c) 1996, 2024 Oracle Corporation.  All rights reserved.
---------------------------------------------------------------
EMD runCollection completed successfully

But following command failed with error ORA-12514,

<AGENT_HOME>/bin/emctl getmetric agent "<target>",osm_instance,Response

[oracle@host01]$ emctl getmetric agent "+ASM1_host01",osm_instance,Response
Oracle Enterprise Manager 24ai Release 1
Copyright (c) 1996, 2024 Oracle Corporation.  All rights reserved.
Status,oraerr
0,Failed to connect: java.sql.SQLRecoverableException: Listener refused the connection with the following error:
ORA-12514\, TNS:listener does not currently know of service requested in connect descriptor

CAUSE

Listener parameter USE_SID_AS_SERVICE_LISTENER is set to on.

Example listener.ora

LISTENER=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER))))        # line added by Agent
LISTENER_SCAN3=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN3))))   # line added by Agent
LISTENER_SCAN2=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN2))))   # line added by Agent
LISTENER_SCAN1=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER_SCAN1))))   # line added by Agent
ASMNET1LSNR_ASM=(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=IPC)(KEY=ASMNET1LSNR_ASM)))) # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_ASMNET1LSNR_ASM=ON       # line added by Agent
VALID_NODE_CHECKING_REGISTRATION_ASMNET1LSNR_ASM=SUBNET # line added by Agent
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN1=ON        # line added by Agent
VALID_NODE_CHECKING_REGISTRATION_LISTENER_SCAN1=OFF     # line added by Agent - Disabled by Agent because REMOTE_REGISTRATION_ADDRESS is set
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN2=ON        # line added by Agent
VALID_NODE_CHECKING_REGISTRATION_LISTENER_SCAN2=OFF     # line added by Agent - Disabled by Agent because REMOTE_REGISTRATION_ADDRESS is set
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER_SCAN3=ON        # line added by Agent
VALID_NODE_CHECKING_REGISTRATION_LISTENER_SCAN3=OFF     # line added by Agent - Disabled by Agent because REMOTE_REGISTRATION_ADDRESS is set
ENABLE_GLOBAL_DYNAMIC_ENDPOINT_LISTENER=ON              # line added by Agent
VALID_NODE_CHECKING_REGISTRATION_LISTENER=SUBNET        # line added by Agent
USE_SID_AS_SERVICE_LISTENER=ON

When the database is an Oracle Database 12c or higher container database, the client must specify a service name in order to connect to it. Setting this parameter to on instructs the listener to use the SID in the connect descriptor as a service name and connect the client to the specified database.

It is helpful for database clients with earlier releases of Oracle Database that have hard-coded connect descriptors. The clients can use this parameter to connect to a container or pluggable database.

SOLUTION

Remove that parameter, reload or restart the listener. If the parameter is needed for application, a dedicated listener with specific port is recommended. Do not user VIP listener for this purpose because VIP listener as local listener in Grid Infrastructure system is shared with all ASM and database instances.