InfoDoc ID | Synopsis | Date | ||
49083 | Fujitsu disk drives use different WWN scheme than traditionally seen | 25 Nov 2002 |
Status | Issued |
Description |
Sun has qualified a new, 10,000 rpm, 72 gig Fujitsu drive. The manufacturing part number for the disk is 390-0098, and the FRU part number for the disk is 540-5408. The disk is currently qualified for use in the Netra 20, SunFire v480 and v880 servers. The drive uses a different wwn scheme than drives previously used by Sun. This may introduce some confusion when using traditional techniques to verify multipathing conditions are available. Lets look at a simple working example within a V880. The system has one Seagate disk in slot 0. There is also a crystal plus card in slot 8 providing a second path to the drive. luxadm display : SLOT DISKS (Node WWN) 0 On (O.K.) 2000002037bd3f11 format: 0. c1t0d0 <SUN18G cyl 7506 alt 2 hd 19 sec 248> /pci@8,600000/SUNW,qlc@2/fp@0,0/ssd@w2100002037bd3f11,0 1. c2t0d0 <SUN18G cyl 7506 alt 2 hd 19 sec 248> /pci@9,600000/pci@2/SUNW,qlc@4/fp@0,0/ssd@w2200002037bd3f11,0 Important Points: a. luxadm reports a WWN of 2000002037bd3f11 b. luxadm prefaces the wwn with a "20". c. format changes 20 to 21 (ssd@w21) for the A loop path. This is the onboard data path. d. format changes 20 to 22 (ssd@w22) for the B loop path. This is the crystal + card data path. e. The last 14 digits remain unchanged. Its easy to look at the WWN 's in format and visualize them as the same disk. Now lets add the new Fujitsu disk to the mix. The disk is added to slot 1 in the v880. Look at the outputs now. luxadm display : SLOT DISKS (Node WWN) 0 On (O.K.) 2000002037bd3f11 1 On (O.K.) 500000e010124620 format: 0. c1t0d0 <SUN18G cyl 7506 alt 2 hd 19 sec 248> /pci@8,600000/SUNW,qlc@2/fp@0,0/ssd@w2100002037bd3f11,0 1. c1t1d0 <SUN72G cyl 14087 alt 2 hd 24 sec 424> /pci@8,600000/SUNW,qlc@2/fp@0,0/ssd@w500000e010124621,0 2. c2t0d0 <SUN18G cyl 7506 alt 2 hd 19 sec 248> /pci@9,600000/pci@2/SUNW,qlc@4/fp@0,0/ssd@w2200002037bd3f11,0 3. c2t1d0 <SUN72G cyl 14087 alt 2 hd 24 sec 424> /pci@9,600000/pci@1/SUNW,qlc@4/fp@0,0/ssd@w500000e010124622,0 Important Differences: a. luxadm reports a WWN of 500000e010124620. b. luxadm prefaces the wwn with a "50" instead of "20" The "50" will never change when the WWN is viewed in format. c. The WWN of the disk will always end in "0" from luxadm. d. The WWN of the disk ends in "1" for the A loop data path. e. The WWN of the disk ends in "2" for the B loop data path. These are NORMAL outputs for the disk! The prefixed naming convention of "20, 21 and 22" is gone. The value will always be 50. The last digit of the disk will determine the data path the drive is being accessed from. "1" is an A loop path, "2" the B loop path. The disks will work with multipath software such as Veritas Volume Manager. Techniques described in FIN IO-790 may apply.
INTERNAL SUMMARY:
SUBMITTER: Daniel Caporale APPLIES TO: Hardware/Disk Storage Subsystem, Storage ATTACHMENTS: