Not able to create diskgroup

Hi Team,

SQL> create diskgroup TSTDG normal redundancy disk 'o/*/DCTST*';

create diskgroup TSTDG normal redundancy disk 'o/*/DCTST*'

*

ERROR at line 1:

ORA-15018: diskgroup cannot be created

ORA-15031: disk specification 'o/*/DCTST*' matches no disks

ORA-15014: path 'o/192.168.10.124;192.168.10.125/DCTST1_CD_04_pceladm01' is not

in the discovery set

ORA-15014: path 'o/192.168.10.124;192.168.10.125/DCTST1_CD_03_pceladm01' is not

in the discovery set

ORA-15014: path 'o/192.168.10.124;192.168.10.125/DCTST1_CD_01_pceladm01' is not

in the discovery set

ORA-15014: path 'o/192.168.10.124;192.168.10.125/DCTST1_CD_05_pceladm01' is not

in the discovery set

ORA-15014: path 'o/192.168.10.124;192.168.10.125/DCTST1_CD_00_pceladm01' is not

in the discovery set