SVRMGR> recover datafile '/home1/oracle/oradata/HNS/rbs01.dbf';
SVMRGR> recover database
but both didnt work.

Later on i saw that file permissions were wrong.

[root@mail HNS]# chown oracle rbs01.dbf
[root@mail HNS]# chgrp oinstall rbs01.dbf

SVRMGR> recover datafile '/home1/oracle/oradata/HNS/rbs01.dbf';
ORA-00279: change 6651886 generated at 01/20/2004 15:37:22 needed for thread 1
ORA-00289: suggestion : /home1/oracle/admin/HNS/arch/arch_1_71654.arc
ORA-00280: change 6651886 for thread 1 is in sequence #71654
Specify log: {=suggested | filename | AUTO | CANCEL}

I kept ON PRESSING enter
Log applied.
ORA-00279: change 6672048 generated at 03/09/2004 21:08:49 needed for thread 1
ORA-00289: suggestion : /home1/oracle/admin/HNS/arch/arch_1_71655.arc
ORA-00280: change 6672048 for thread 1 is in sequence #71655
ORA-00278: log file '/home1/oracle/admin/HNS/arch/arch_1_71654.arc' no longer needed for this recovery
Specify log: {=suggested | filename | AUTO | CANCEL}

Log applied.
ORA-00279: change 6672163 generated at 03/09/2004 21:20:52 needed for thread 1
ORA-00289: suggestion : /home1/oracle/admin/HNS/arch/arch_1_71656.arc
ORA-00280: change 6672163 for thread 1 is in sequence #71656
ORA-00278: log file '/home1/oracle/admin/HNS/arch/arch_1_71655.arc' no longer needed for this recovery
Specify log: {=suggested | filename | AUTO | CANCEL}

Log applied.
ORA-00279: change 6673804 generated at 03/09/2004 21:39:03 needed for thread 1
ORA-00289: suggestion : /home1/oracle/admin/HNS/arch/arch_1_71672.arc
ORA-00280: change 6673804 for thread 1 is in sequence #71672
ORA-00278: log file '/home1/oracle/admin/HNS/arch/arch_1_71671.arc' no longer needed for this recovery
Specify log: {=suggested | filename | AUTO | CANCEL}

i did it many times and then i got this message

Log applied.
Media recovery complete.

alter database open;
statement processed