Понадобилось добавить места в ASM на кластере. Логичней расширить уже существующие луны чем плодить дополнительные диски. Расширил на СХД, refresh дисков и расширение тома прошло успешно на первой ноде. А вот на второй ноде фигвам — при resfresh дисков ASM ругнулся:

Mon Feb 25 18:55:30 2013
Errors in file D:APPBASEdiagrdbmsrtlrtl2tracertl2_ora_9328.trc:
ORA-27070: async read/write failed
OSD-04006: ReadFile() failure, unable to read from file
O/S-Error: (OS 2) The system cannot find the file specified.
WARNING: Read Failed. group:2 disk:4 AU:29757 offset:147456 size:8192
WARNING: failed to read mirror side 1 of virtual extent 27443 logical extent 0 of file 282 in group [2.1970330447] from disk DATA_0004  allocation unit 29757 reason error; if possible, will try another mirror sid
Errors in file D:APPBASEdiagrdbmsrtlrtl2tracertl2_ora_9328.trc:
ORA-27070: async read/write failed
OSD-04006: ReadFile() failure, unable to read from file
O/S-Error: (OS 2) The system cannot find the file specified.
WARNING: Read Failed. group:2 disk:5 AU:29757 offset:147456 size:8192
WARNING: failed to read mirror side 2 of virtual extent 27443 logical extent 1 of file 282 in group [2.1970330447] from disk DATA_0005  allocation unit 29757 reason error; if possible, will try another mirror sid

и в v$asm_disk на месте одного диска появилось два — старый со старым размером и нулевым путем, mount_status missed и новый с новым размером, правильным путем но в mount_status closed. После чего база и asm на этой ноде ушли в down а на первой ноде ASM начал процесс ребилда.

Вот что нашел:

O/S-Error: (OS-2) The system cannot find the file specified.
Cause: If a disk is disabled at the operating system level and enabled again, some of the Oracle ASM operations such as CREATE DISKGROUP, MOUNT DISKGROUP, ADD DISK, ONLINE DISK, or querying V$ASM_DISK fail with the error:
OS Error: (OS-2) The system cannot find the file specified.

This happens when a previously mounted disk is assigned a new volume ID by the operating system. When Oracle ASM uses the old volume ID, it fails to open the disk and signals the above error.

Action: Use ASMTOOL to restamp the disk and update the volume ID used by Oracle ASM.

Похоже windows сменила VolumeID и ASM потерял диск.

Решается как написано asmtool -addprefix