Error:
ERROR: diskgroup DG02 was not mounted
ORA-15032: not all alterations performed
ORA-15017: diskgroup "DG02" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "DG02"
ORA-15080: synchronous I/O operation to a disk failed
ORA-27061: waiting for async I/Os failed
Linux-x86_64 Error: 5: Input/output error
Additional information: -1
Additional information: 4096
WARNING: Read Failed. group:0 disk:0 AU:0 offset:0 size:4096
ERROR: no read quorum in group: required 2, found 0 disks
ERROR: -9(Error 27061, OS Error (Linux-x86_64 Error: 5: Input/output error
ERROR: diskgroup DG02 was not mounted
ORA-15032: not all alterations performed
ORA-15017: diskgroup "DG02" cannot be mounted
ORA-15063: ASM discovered an insufficient number of disks for diskgroup "DG02"
ORA-15080: synchronous I/O operation to a disk failed
ORA-27061: waiting for async I/Os failed
Linux-x86_64 Error: 5: Input/output error
Additional information: -1
Additional information: 4096
WARNING: Read Failed. group:0 disk:0 AU:0 offset:0 size:4096
ERROR: no read quorum in group: required 2, found 0 disks
ERROR: -9(Error 27061, OS Error (Linux-x86_64 Error: 5: Input/output error