I created a script to assist customers with creating luns and presenting it up to Oracle ASM, since I was finding that there is a large disconnect in how people think about device IDs and multipath IDs. Also, there was alot of confusion in the communication between the groups of a company when a DBA requested a new LUN.
Blog post about the script and where I will keep up to date copies, and some more information on it.
http://www.jk-47.com/2012/07/scripted-netapp-lun-creation-oracle-asm-addition/
Typically, if a customer wanted to add a new LUN to an Oracle database server, the steps would look like this:
- DBA asks SAN admin for a LUN
- SAN admin creates LUN, presents it to server
- SAN admin tells Linux/System Admin it’s presented
- Linux/System Admin rescans the SCSI bus to discover the lun
- Linux/System Admin does all the multipath mumbojumbo to create the /dev/mapper crap
- Linux/System Admin fdisks partition (aligned to SAN I hope)
- DBA uses /etc/init.d/oracleasm to tag the new lun to ASM
Thats just too many steps... there really only needs to be 1 person in the mix. After all, thats what SnapDrive is made for...
This is a starting point script only. No guarantees are given. If you give it the name of a lun which already exists, it WILL fdisk it anyway. I have modified this for some environments to create everything, all luns, all vols, all tablespaces, etc etc. Think of it as a starting point. Again, see my blog for more information and some disclaimers.
Example usage and output:
Script Name: makemount.sh
Input 1: Tablespace Name
Input 2: Volume Identified Number
Input 3: Lun Size
Input 4: Lun Identified Number
Input 5: Controller Name
[root@oraclebox bin]# ./makemount.sh OCR1 1 5 D netappc1
LUN netappc1:/vol/OraOCR1Vol1/OraOCR11_D.lun ... created
mapping new lun(s) ... done
discovering new lun(s) ... done
LUN to device file mappings:
- netappc1:/vol/OraOCR1Vol1/OraOCR11_D.lun => /dev/sdal, /dev/sdam
Getting lun info
Getting Multipath information
Partitioning Disk
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): Command action
e extended
p primary partition (1-4)
Partition number (1-4): First cylinder (1-652, default 1): Last cylinder or +size or +sizeM or +sizeK (1-652, default 652): Using default value 652
Command (m for help):
Expert command (m for help): Partition number (1-4): New beginning of data (63-10474379, default 63):
Expert command (m for help): The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 22: Invalid argument.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
Disk /dev/mapper/360a980006473444b48346b796e6c5749: 5368 MB, 5368709120 bytes
255 heads, 63 sectors/track, 652 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/mapper/360a980006473444b48346b796e6c5749p1 1 652 5237158 83 Linux
Partition 1 has different physical/logical beginnings (non-Linux?):
phys=(0, 1, 1) logical=(0, 1, 2)
kpartx on disk
add map 360a980006473444b48346b796e6c5749p1 (253:40): 0 10474316 linear /dev/mapper/360a980006473444b48346b796e6c5749 64
CREATEDISK in /etc/init.d
/etc/init.d/oracleasm createdisk OCR1_D /dev/mapper/360a980006473444b48346b796e6c5749p1
Marking disk "OCR1D" as an ASM disk: [ OK ]
Cleaning up
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That's it. You have your lun.. and the DBA can see it in ASM to add to a diskgroup and mount up.
R. Jarett Kulm
VCP5, NetApp NCIE-SAN, F5 CSP,
EMC Velocity SE, NBU7 STS, etc etc etc...
Professional Services Engineer
H.A. Storage Systems, Inc.
