Hi, Actually, when you have 2 storage boxes and 1 of them failed then you only have 50% chance that your failover will work. This because one of the storage boxes will hold 2 voting disks and if this san failes the entire rac cluster will fail. With 11gR2 the votings disks are placed on the asm disks, but are not visible as asm files. Instead (to my knowledge) they are placed on a fixed region of the disk. When installing the clusterware using the universal installer, Oracle will ask you to specify 3 asm disks to store the voting disks when selecting normal redundancy (if you choose to store the voting disks on asm). Following output comes from an 11gR2 rac cluster: [grid@arsvorats1 ~]$ crsctl query css votedisk ## STATE File Universal Id File Name Disk group -- ----- ----------------- --------- --------- 1. ONLINE 7855e73b3d2a4fb3bf901beecad62093 (/dev/oracle/asm_clfilests1p1) [DG_CLUSTER] 2. ONLINE 213259f135934f27bf86b91559a44df5 (/dev/oracle/asm_clfilests2p1) [DG_CLUSTER] 3. ONLINE 1b12d9dc6d2b4fb8bfe63b365e2db555 (/dev/oracle/asm_clfilests3p1) [DG_CLUSTER] Located 3 voting disk(s). [grid@arsvorats1 ~]$ ocrcheck Status of Oracle Cluster Registry is as follows : Version : 3 Total space (kbytes) : 262120 Used space (kbytes) : 2800 Available space (kbytes) : 259320 ID : 1074808153 Device/File Name : +DG_CLUSTER Device/File integrity check succeeded Device/File not configured Device/File not configured Device/File not configured Device/File not configured Cluster registry integrity check succeeded Logical corruption check bypassed due to non-privileged user [grid@arsvorats1 ~]$ export ORACLE_SID=+ASM1 [grid@arsvorats1 ~]$ asmcmd ASMCMD> ls DG_CLUSTER/ DG_DWHTS_DATA/ DG_FRA/ ASMCMD> cd DG_CLUSTER ASMCMD> ls arclorats/ ASMCMD> cd arclorats ASMCMD> ls ASMPARAMETERFILE/ OCRFILE/ ASMCMD> cd OCRFILE ASMCMD> ls -l Type Redund Striped Time Sys Name OCRFILE MIRROR COARSE JUL 10 00:00:00 Y REGISTRY.255.721844181 SQL> set linesize 120 SQL> column full_alias_path format a70 SQL> column file_type format a15 SQL> select concat('+'||gname, sys_connect_by_path(aname, '/')) SQL> full_alias_path, 2 system_created, alias_directory, file_type 3 from ( select b.name gname, a.parent_index pindex, a.name aname, 4 a.reference_index rindex , a.system_created, a.alias_directory, 5 c.type file_type 6 from v$asm_alias a, v$asm_diskgroup b, v$asm_file c 7 where a.group_number = b.group_number 8 and a.group_number = c.group_number(+) 9 and a.file_number = c.file_number(+) 10 and a.file_incarnation = c.incarnation(+) 11 ) 12 where alias_directory = 'N' 13 and system_created = 'Y' 14 and file_type like 'OCR%' 15 start with (mod(pindex, power(2, 24))) = 0 16 and rindex in 17 ( select a.reference_index 18 from v$asm_alias a, v$asm_diskgroup b 19 where a.group_number = b.group_number 20 and (mod(a.parent_index, power(2, 24))) = 0 21 ) 22 connect by prior rindex = pindex; FULL_ALIAS_PATH S A FILE_TYPE ---------------------------------------------------------------------- - - --------------- +DG_CLUSTER/arclorats/OCRFILE/REGISTRY.255.721844181 Y N OCRFILE Regards, Freek D'Hooge Uptime Oracle Database Administrator email: freek.dhooge@xxxxxxxxx tel +32(0)3 451 23 82 http://www.uptime.be disclaimer: www.uptime.be/disclaimer -- From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Michael Elkin Sent: donderdag 5 augustus 2010 6:53 To: oracle-l Subject: ASM - storage virtualization solution Dear list members, I would like to know if someone has an experience in the following solution. Configuration example : 2 IBM servers that are located on different blade chassis are connected to 2 separate IBM storages. Each blade server has a fiber connection to each storage. On each storage we allocate a lun and each server can see all allocated luns on both storages. The idea is to use ASM on each node with a mirroring and create a disk group with ASM "Normal redundancy" using Luns from both storages. This can give us maximum availability: 1. For DB or node failure we use RAC 2. Blade servers are located on different chassis , so we do not loose all RAC nodes in case of a complete blade chassis failure 3. In case of a storage failure we have a second storage that is mirrored by ASM and most important is always active and is connected to all RAC servers, this means there is no need to perform any manual operations to switch this storage to an active mode and connect RAC servers to it. In general ASM can serve here as a storage virtualization solution. Thank you. -- Best Regards Michael Elkin -- //www.freelists.org/webpage/oracle-l