How could we start Oracle database in Oracle Exadata which's celldisk has proactive failure?

I am trying to open exadata machine but it has error. That EXADATA  Oracle Sun Fire X4720 M3 SAS, Oracle 11gr2 RAC database installed. I was examining celldisks. When i gave command list griddisk I see that result. cellcli> list griddisk     DATA_DM01_00_mycelldisk01 proactive failure We dropped celldisk, we can't recreated griddisk and celldisk, it has error. we can't replace it because we can't get any disk from anywhere. I need to open that exadata and i plan to open database without that celldisk. should i drop physicaldisk? cellcli> list physicaldisk     20:0 KERMXM warning - proactive failure, poor performance when I give command srvctl start database -d mydb it gives error. ORA-15040: diskgroup is incomplete ORA-15066: offlining disk "0" in group DATA_DM01 may result in a data loss ORA-15042: ASM disk "0" is missing from group number "1" Could i delete disk "0" which is proactive failure and continue my system? Thanks