Persitent Binding for HBA Card

Persistent binding : As the name implies persistent binding enables LUNs zoned from a Storage frame will be assigned with a specific target ID. Now next question which may pops up in your mind "Why do we need that"?

I don't have any strong answer for it. After googling, got few clarifications which are not much convincing.

Below are the few points which i feel could be a reasonable answer for the above question.

1. In a cluster environment where the same LUN is assigned to multiple machine should be configured with persistent target ID.

2. Its a recommended steps for emulex branded HBA card where drivers software are provided by Emulex and same applies for Q Logic branded card.

Here in this, i would be taking only Emulex and Qlogic card as these cards are the most commonly used card on Solaris Box.

NOTE : You do not need to configure persistent binding for Sun Branded Emulex and Qlogic card. 

So HBA cards are categorized as Sun-branded and Sun-non-branded.

Below are the tips to identify the sun-branded and non-branded qlogic and emulex card.

Emulex Card:

LPxxxxxx-S are SUN Emulex HBA Cards  (ie has a “-S” for Sun at end).

For Solaris 10 fcinfo hba-port would provide you the details and for previous version of solaris prtpicl command can be used to get the HBA details

If you see any of the following references they are NON-SUN HBA Cards:

NON-SUN Qlogic:

• qlaxxxx
• QLGC,qla
• QLGC,qlc
• SUNW,qla

NON-SUN Emulex:

• emlx (emlxs is SUN)
• lpfc
  
  Click on the below link for the detailed explanation.
  
  Identify HBA card
  
  So we have got some idea on HBA cards identification now lets go ahead and configure the persistent for emulex card. As i have previously mentioned that persistent binding is needed only for SUN non-branded emulex card.
  
  To configure persistent binding, there are 2 files needed to be modified.
  
  /kernel/drv/lpfc.conf
  /kernel/drv/sd.conf
  
  lpfc.conf - Kernel configuration file for lpfc driver modules
  sd.conf - kernel configuration file for sd driver module
  
  lpfc.conf file is where you configure the persistent binding and sd.conf is where you should add enough entry to allow OS to scan for more devices.
  
  For persistent binding you need to find the HBA card instance you can easily determine this by using lputil commands
  
  Here is an example
  
  bash-3.00# /usr/sbin/lpfc/lputil
  LightPulse Common Utility for Solaris/SPARC. Version 2.0a13 (1/3/2006).
  Copyright (c) 2005, Emulex Corporation
  
  Emulex Fibre Channel Host Adapters Detected: 3
  Host Adapter 0 (lpfc3) is an LP11002-E (Ready Mode)
  Host Adapter 1 (lpfc4) is an LP11002-E (Ready Mode)
  Host Adapter 2 (lpfc2) is an LP9802 (Ready Mode)
  
  
  As you can see above there are 3 cards. LP11002-E looks like a dual port card that can be confirmed by looking at /etc/path_to_inst file . Here is extract from the the file
  
  
  "/pci@1c,600000/lpfc@1,1" 1 "emlxs"
  "/pci@1c,600000/lpfc@1,1" 1 "lpfc"
  "/pci@1c,600000/lpfc@1,1/fp@0,0" 1 "fp"
  "/pci@1c,600000/fibre-channel@1" 3 "lpfc"
  "/pci@1c,600000/fibre-channel@1,1" 4 "lpfc"
  "/pci@1d,700000/lpfc@2" 2 "emlxs"
  "/pci@1d,700000/lpfc@2" 2 "lpfc"
  "/pci@1d,700000/lpfc@2/fp@0,0" 2 "fp"
  
  From the above 
•  
• "/pci@1c,600000/fibre-channel@1" 3 "lpfc"
  "/pci@1c,600000/fibre-channel@1,1" 4 "lpfc"
  
  
  See the physical path of the lpfc which is same with the instance as 3 and 4 so its a single HBA card having dual port so lpfc3 and lpfc4 is the instance of dual port HBA card.
  
  Sample sd.conf file:
  
  name="sd" parent="lpfc" target=0 lun=0 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=1 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=2 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=3 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=4 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=5 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=6 hba="lpfc0";
  name="sd" parent="lpfc" target=0 lun=7 hba="lpfc0";
  
  name="sd" parent="lpfc" target=1 lun=0 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=1 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=2 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=3 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=4 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=5 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=6 hba="lpfc1";
  name="sd" parent="lpfc" target=1 lun=7 hba="lpfc1";
  
  
  
  
  
  Now in the above output assigning lun no is a tricky one. You need to work with storage team for it. Get the HEX code for each LUN and convert it to decimal which needs to be specified as lun no.
  
  Another example of /etc/path_to_inst
  
  > grep -i lpfc /etc/path_to_inst
  "/pci@1e,600000/pci@0/pci@1/pci@0/pci@8/fibre-channel@1" 0 "lpfc"
  "/pci@1e,600000/pci@0/pci@1/pci@0/pci@8/fibre-channel@1,1" 1 "lpfc"
  "/pci@1e,600000/pci@0/pci@8/fibre-channel@0" 4 "lpfc"
  "/pci@1e,600000/pci@0/pci@8/fibre-channel@0,1" 5 "lpfc"
  "/pci@1f,700000/pci@0/pci@2/pci@0/pci@8/fibre-channel@2" 2 "lpfc"
  "/pci@1f,700000/pci@0/pci@2/pci@0/pci@8/fibre-channel@2,1" 3 "lpfc"
  "/pci@1f,700000/pci@0/pci@9/fibre-channel@0" 6 "lpfc"
  "/pci@1f,700000/pci@0/pci@9/fibre-channel@0,1" 7 "lpfc"
  
  From the above you can find out that there 4 emulex dual ports HBA cards