Chapter 19. FC configuration 1 - Emulex HBA boot BladeServer from SAN
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Draft Document for Review August 30, 2007 12:59 am
7065FC_Config1.fm
On the DS3400, create the host and HBA port, create a logical drive of the size required for
the boot partition (or use an existing free logical drive), and assign the logical drive to the
host, specifying LUN 0.
19.3 Enabling boot from SAN with Emulex adapters
Now we will configure the HBAs for booting from SAN. In this sample configuration we show
this on the Emulex BladeCenter 4 GB HBAs.
19.3.1 Set port switch speed
Depending on the switch module used in the BladeCenter, you should set the switch ports
associated with the Emulex HBAs to a fixed negotiation speed of 4GB/s, rather than the
default of Auto. This is required on the QLogic or McData 4Gb/s 10/20 port switch modules.
Consult your switch documentation for informaton on how to do this. On our McData switch,
use
telnet
to open a connection to the switch. We then use the commands shown in
Example 19-1 to change the port speed.
Example 19-1 Set fixed speed on port
admin start
config edit
set port 5 speed 4
config save
19.3.2 Enable adapter BIOS
By default, the adapter BIOS is disabled. For boot from SAN, the BIOS must be enabled so
that the boot devices can be properly selected.
1. Enter the Adapter BIOS (as described in “FC Emulex HBA” on page 139). From the screen
in Figure 8-9 on page 140, select the WWN which was assigned the logical drive in 19.2,
“Configuring the DS3400” on page 448).
2. From the port menu (Figure 8-10 on page 140), type 2 and press Enter to open
Configure This Adapter’s Parameters (Figure 19-13 on page 450).
Notes:
In order to successfully install the operating system there should only be a single
unique path from the BladeServer to the boot LUN via the storage controller that
currently owns the boot LUN. Otherwise the operating system installation will fail due to
lack of multipath support in the OS. Additional paths can be enabled after the operating
system has been successfully installed, including the multipath driver.
The boot device always has to be LUN 0.
Note: In our configuration, we are using Emulex HBAs, however HBAs from QLogic are
also supported, as per the Web site. The BIOS utility procedures are similar to those
described in Chapter 21, “FC configuration 3 - Linux SAN boot with System x 3755” on
page 493
