persistent binding

Hi,

I am a sysadmin that is new to the area of storage and SAN. Can anyone
direct me to a good article about persistent binding - what it is and
how to do it? Mainly for solaris (jni/qlogic) but other OS's also.

Also is persistent binding valid only for disks or can it be used for
tape drives/libraries also?

Thank you,

Jhn

The persistent binding feature allows you to control the devices that are
to be presented to the system.

The HBA driver detects all devices attached to the host bus adapters
(HBAs). Global automapping assigns a binding type, target ID, SCSI bus and
SCSI ID to the device. The binding type, SCSI bus and SCSI ID may change
when the system is rebooted. When persistent binding is applied to one of
these targets, the binding type, SCSI bus and SCSI ID remain the same,
whether the system is rebooted or whether Global Automap All Targets is
subsequently disabled (enabled by default).

The binding information is permanent. The driver refers to the binding
information at bootup.

Persistent binding permanently maps a device to the following
Binding types:

1) World wide port name (WWPN) - e.g. Tape/Disk port name
2) World wide node name (WWNN) - e.g. Tape/Disk node name
A node can have multible ports, e.g. one Tape drive with two
fc-ports,
this Tape will have one unique WWNN and two WWPNs
3) Destination identifier (D_ID) - e.g. this is the 24bit address of the
fc-switch
port your device is connected to.


Persistent binding is valid for disks, tapes, library controllers ...

HOW-TO-DO:

1) Solaris

You have to edit:

- Emulex: /kernel/drv/elxcfg.conf
you can use vi or lputil-Tool from emulex for that
- Qlogic: /kernel/drv/qla2x00.conf
you can use vi or SANsurfer Toolkit from Qlogic for that
- JNI: /kernel/drv/jnic.conf (or fcaw.conf, or jnic146x.conf)
you can use vi or ezfibre-Tool from JNI for that

All config files have good examples on how to do it via an editor.
After finished all changes, I recommend to boot -r your system.

2) Windows

Persistent bindings are stored in the registry. You should use the
vendors tools to edit them:

- Emulex: HBAnywhere
- Qlogic: SANsurfer Toolkit
- JNI: EZfibre

But be warned, Windows form of persistent binding is not what you get
with any other Unix form, e.g. if you have lets say three tapes (\\.\tape0
to \\.\tape2)
with persistent binding and lost \\.\tape1, do a reboot - windows comming
up with \\.\tape0 and \\.\tape1 (and not \\.\tape0 and \\.\tape2!)

3) Linux

Please refer to HBA vendor pages for that, they all have different ways to

do that. All of them have well documented manuals on that topic.

René
--
------------------------------------------------------
**** Complex Systems tend to fail in complex ways ****
------------------------------------------------------
Rene Koehnen-Wiesemes

wrote:

Hi,

I am a sysadmin that is new to the area of storage and SAN. Can anyone
direct me to a good article about persistent binding - what it is and
how to do it? Mainly for solaris (jni/qlogic) but other OS's also.

Also is persistent binding valid only for disks or can it be used for
tape drives/libraries also?

Thank you,

Jhn

Thank you for answering my questions.

Rene Koehnen-Wiesemes wrote in message ...


with any other Unix form, e.g. if you have lets say three tapes (\\.\tape0
to \\.\tape2)
with persistent binding and lost \\.\tape1, do a reboot - windows comming
up with \\.\tape0 and \\.\tape1 (and not \\.\tape0 and \\.\tape2!)

Doesnt that sort of defeat the purpose of persistent binding?
Thankfully I wont have to deal with windows in the near future!!