one rac node failed to startup after san storage disk corrupted

Hello

we are using oracle database 10.2.0.1 (RAC with two instaces).

And using one diskgroup called (DATA) with two disks (DATA_0000,DATA_0001)

one of the instances is mounted (working fine +ASM1) but the other one not mounted (+ASM2)

when I tried to mount it force it gives me the following error:-

sql> alter diskgroup DATA mount;

alter diskgroup DATA mount

*

ERROR at line 1:

ORA-15032: not all alterations performed

ORA-15040: diskgroup is incomplete

ORA-15042: ASM disk "1" is missing

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Here is some details about our system:-

sql>select NAME,GROUP_NUMBER,STATE,TYPE from  v$asm_diskgroup;

NAME          GROUP_NUMBER             STATE                 TYPE