ORA-01565: error in identifying file / ORA-27037: unable to obtain file status.

ORA-01565: error in identifying file / ORA-27037: unable to obtain file status.
When trying to create pfile from spfile getting below error.

ORA-01565: Unable to open Spfile /u01/app/oracle/product/11.2.0/db_1/dbs/spfile$SID.ora.

SQL> create pfile='/d01/oracle/initsetting.ora' from spfile;
create pfile='/d01/oracle/initsetting.ora' from spfile

ERROR at line 1:
ORA-01565: error in identifying file '?/dbs/spfile@.ora'
ORA-27037: unable to obtain file status
SVR4 Error: 2: No such file or directory
Additional information: 3

Cause: Database is not running with spfile,It is running with memory.
issue seen  while doing rman duplicate clone or Unexpectedly spfile/pfile dropped/missing while database is up and running fine..

Solution:-

SQL> create pfile='/d01/oracle/initsetting.ora' from memory;

File created.