How to resolve Could not validate ASMSNMP password due to following error- "ORA-01031: insufficient privileges"

Oracle 11g R2 grid

goto grid home /bin

[grid@node1 bin]$ orapwd file=/u01/app/11.2.0/grid/dbs/orapw+ASM password=oracle_4U

[grid@node1 dbs]$ scp orapw+ASM Node2:/u01/app/11.2.0/grid/dbs/

[grid@node1 dbs]$ scp orapw+ASM Node3:/u01/app/11.2.0/grid/dbs/

Login in to Oracle database as

export ORACLE_SID=+ASM1
export ORACLE_HOME=/u01/app/11.2.0/grid

[grid@node1 bin]$ sqlplus / as sysasm

SQL>create user asmsnmp identified by oracle_4U;

SQL> grant sysdba to asmsnmp;