How to change ASMSNMP user password in Oracle RAC Database.

        The ASMSNMP user is an Oracle ASM user with privileges to monitor Oracle ASM instances. The ASMSNMP user password is required to configure monitoring. Following are the steps by step guides to change asmsnmp password if you forgot.

        The ASMSNMP user password is required while creating an Oracle RAC database. If you forgot, then you can follow the below steps to reset asmsnmp user password.

        Log in as grid user or export to  ORACLE ASM-HOME and SID as ASM instance if configured both grid and oracle in one user.

Method 1: Use alter user command.

        The command requires the SYSASM privilege to run. A user logged in as SYSDBA cannot change their password using this command.

Connecting to the ASM instance and executing an alter user

. oraenv <<< +ASM1

$ sqlplus / as sysasm

SQL> select * from v$pwfile_users;

USERNAME                        SYSDB  SYSOP  SYSAS
------------------------------  -----  -----  -----
SYS                             TRUE   TRUE   TRUE
ASMSNMP                         TRUE   FALSE  FALSE

SQL> ALTER USER asmsnmp IDENTIFIED BY <new_password>;

SQL> exit

Method 2: Using orapwusr command. 

The orapwusr attempts to update passwords on all nodes in a cluster. 

Connect as grid user, and export ASM instance variables.

. oraenv <<< +ASM1
$ asmcmd
ASMCMD> lspwusr
Username  sysdba  sysoper  sysasm
     SYS    TRUE     TRUE    TRUE
 ASMSNMP    TRUE    FALSE   FALSE

ASMCMD> lspwusr
Username  sysdba  sysoper  sysasm
     SYS    TRUE     TRUE    TRUE
 ASMSNMP    TRUE    FALSE   FALSE

The username is case-sensitive while using orapwusr command, use ASMSNMP in upper case.
ASMCMD> orapwusr
usage: orapwusr { { { --add | --modify [--password] }[--privilege {sysasm|sysdba|sysoper} ] } | --delete } user
help:  help orapwusr
ASMCMD> orapwusr --modify --password ASMSNMP
Enter password: *******



-- 12c and above.

[oracle@host19c +ASM1]$ asmcmd 
ASMCMD> lspwusr 
       Username sysdba sysoper sysasm  
            SYS   TRUE    TRUE   TRUE  
CRSUSER__ASM_001   TRUE   FALSE   TRUE  
        ASMSNMP   TRUE   FALSE  FALSE  

ASMCMD> help orapwusr 
usage: orapwusr {--add | --modify | --delete | --grant {sysasm|sysdba|sysoper} | --revoke {sysasm|sysdba|sysoper} } <user> 
 ASMCMD> orapwusr --modify ASMSNMP 
Enter password: ******** 
ASMCMD>