Error encountered while connecting DB instance from root user.
Could you help me here
Alert Log file
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Thu Jan 03 08:58:43 2019
Errors in file /opt/oracle/diag/rdbms/sr1rsd20//trace/_ora_25252.trc:
ORA-15186: ASMLIB error function = [asm_init], error = [18446744073709551611], mesg = [Driver not installed]
ERROR: error ORA-15186 caught in ASM I/O path
Errors in file /opt/oracle/diag/rdbms/<Instance>/trace/<instance>_ora_25252.trc:
ORA-00202: control file: '+DATADG1/sr1rsd20/controlfile/current.1514.777483441'
ORA-15081: failed to submit an I/O operation to a disk