Creating Linux Partitions for CLARiiON
Creating a properly offset slab of disk for Linux systems on your CLARiiON is not just a matter of creating a partition using the default fdisk values. The reason for this is that disk management utilities for Intel based systems generally write 63 sectors of metadata directly at the beginning of the LUN. The addressable space begins immediately after these initial sectors causing the CLARiiON to cross disks, especially when writing larger IO because it doesn’t match up with the stripe element size (usually 64k).
To get around this, you have to align the partition in such a way that it will start writing data on a sector that will mesh up nicely with the stripe element size. In this case, 128. Below is an example of how I create partitions on our CLARiiON for Linux systems. Check out the EMC Best Practices for Fibre Chanel storage white paper for more detail.
/sbin/fdisk /dev/emcpowera 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. The number of cylinders for this disk is set to 39162. There is nothing wrong with that, but this is larger than 1024, and could in certain setups cause problems with: 1) software that runs at boot time (e.g., old versions of LILO) 2) booting and partitioning software from other OSs (e.g., DOS FDISK, OS/2 FDISK) Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite) Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4): 1 First cylinder (1-39162, default 1): Using default value 1 Last cylinder or +size or +sizeM or +sizeK (1-39162, default 39162): Using default value 39162 Command (m for help): x Expert command (m for help): b Partition number (1-4): 1 New beginning of data (63-629137529, default 63): 128 Expert command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. Syncing disks.
Solaris 8 SAN Frustrations
Getting Solaris 8 to light up a Qlogic QLA2310 Fibre Channel card using the SUNWqlc and SUNWqlcx drivers can be frustrating enough, but the headaches are only beginning if you want to connect it to a SAN and you don’t have all the right packages installed.
Last week, I installed the QLA2310 in a Sun Fire V210 running Solaris 8. I installed the latest versions of SUNWqlc, SUNWqlcx and SUNWsan. After doing a reboot -- -r, the system came up and attached the driver to the card. I zoned it in the fabric and logged into Navisphere, where the WWN showed up, but neither Power Path or the Navisphere host agent could communicate with the CLARiiON. I also could not see any of the LUNS I had presented.
I thought it was strange that the CLARiiON could see the host, but the host could not see the CLARiiON.
I ran:
luxadm -e port
Which returned:
Found path to 1 HBA ports
/devices/pci@1d,700000/SUNW,qlc@1/fp@0,0:devctl CONNECTEDClearly, it could see the HBA.
I ran:
ls -l /dev/cfg
total 8
lrwxrwxrwx 1 root root 38 Nov 30 14:31 c0 ->
../../devices/pci@1e,600000/ide@d:scsi
lrwxrwxrwx 1 root root 39 Nov 30 14:31 c1 ->
../../devices/pci@1c,600000/scsi@2:scsi
lrwxrwxrwx 1 root root 41 Nov 30 14:31 c2 ->
../../devices/pci@1c,600000/scsi@2,1:scsi
lrwxrwxrwx 1 root root 48 Dec 4 13:49 c3 ->
../../devices/pci@1d,700000/SUNW,qlc@1/fp@0,0:fcThe card was C3… This becomes useful later when we have to config it.
I ran:
cfgadm -al -o show_FCP_dev
Which retuned:
cfgadm: Configuration administration not supported
There it was… I didn’t have the complete SAN package installed. I hadn’t done this in a few years, so I had forgotten all the packages I had to add to get the Sun SAN package working correctly… There are many.
Happily, Sun has now packaged them in a nice “SAN_4.4.12_install_it.tar.Z”, which you can get from their website if you have a username. It installs everything for you in the right order.
The only thing left to do was another reboot -- -r and run cfgadm -c configure c3 to config the device. After this everything started working nicely.
Little Known CLARiiON Facts and Trivia
I’ve just returned from EMC training in MA, where we learned a wealth of information about how to use the array, but also some interesting background information about the device itself.
First, the name CLARiiON has some interesting history. Before EMC was EMC, it was Data General, who had a 16-bit minicomputer called the NOVA. DG later came up with new product which the engineers had named the NOVAII. The marketing group, not wanting to recycle the “NOVA” name, insisted that a new name be chosen. The engineers, always wanting to get their way in the end, came up with a anagram “AViiON” by reversing the letters, and cleverly placing the two “ii’s” in the middle. The CLARiiON is simply a derivative of this naming convention.
Secondly, most people know that the operating system of the CLARiiON is called “FLARE”, but it is not commonly known that this is actually an acronyms that stands for Fibre Logic Array Runtime Environment.
It is also fairly common knowledge that one can access “Engineering Mode” on a CLARiiON by pressing Ctl,shft, and f12 and entering the password “messner”. The story behind this password, however, is that the engineering group at the time were avid mountain climbers and chose the password in honor of Reinhold Messner, the first person to climb Everest without the use of oxygen. Apparently the password before that was “pink floyd”, but the marketing group didn’t approve and made them change it.
Problems Registering Solaris Hosts With QLA 2310 HBAs in Navasphere
Sun Microsystems likes the QLA 2310 Fiber Channel HBA. It’s only a 2Gig card, but it works with the Sun native driver, which makes it wonderful for us Solaris Administrators. Unfortunately, it does not integrate perfectly with EMC CLARiiON SANs because it does not register properly with Navasphere. Even if you manually register the host, the LUNs will not be presented to the host because the agent can’t pass commands to the array.
To remedy this situation on my Solaris 8 host, I used the following procedure:
Edit the /etc/system file and add the following line:
set fcp:ssfcp_enable_auto_configuration=1
Next, I rebooted my Solaris host with the “-r” flag:
reboot -- -r
Next I checked Navisphere to make sure my paths have logged in. They were, so I logged into the Solaris host and ran the following commands:
cfgadm
devfsadm
format
I then saw the storage that was presented to my host. Finally, I restarted the Navisphere agent and started using my new LUNs.
