HP Booting Linux X86 And X86 64 Systems Manual

							 
Booting Linux x86 and x86_64 systems from a Storage 
Area Network with Device Mapper Multipath 
Enabling the High Availability feature for Operating System Partitions 
Fifth Edition 
 
Document Overview ........................................................................\
...................................................  2 
Intended Audience .......................................................................\
..................................................  2 
Assumptions .......................................................................\
....................................................... .... 2 
Introduction  .......................................................................\
....................................................... ......... 2 
Supported Configuration  .......................................................................\
.............................................  2 
Configuring boot from SAN .......................................................................\
.........................................  3 
Configuring the HBA/NIC ROM for High Availability of Boot device ................................................... 3 
Setting up the storage arrays .......................................................................\
................................  3 
Setting up the host systems .......................................................................\
...................................  3 
Configuring HBA/NIC ROM ........................................................................\
................................  5 
Installing the operating systems .......................................................................\
..................................  18 
Enabling the Device Mapper multipath feature ........................................................................\
.........  18 
Recommended configuration on RHEL operating system ................................................................ 18 
Recommended configuration on SLES operating system  .................................................................  22 
Additional Information ........................................................................\
..............................................  29 
  
						

							Document Overview 
This white paper helps you understand the concepts and configuration of boot from SAN and 
enabling multipath features for the Root partition on SAN in deployments using Device Mapper 
multi-path. It includes recommendations for im plementing and configuring operating system 
installation partitions to enable the Device Mapper multipath feature on your Linux server. 
 
Intended Audience 
This document is intended for users who would be  implementing the high availability features of 
Boot-from-SAN and Root partition for the Linux op erating system with Device Mapper multipath. 
 
Assumptions 
This document assumes that the user  is familiar with the following: 
 
•   HP Fibre Channel Host Bus Adapters (HBAs) for Linux servers 
•   HP SAS Host Bus Adapters 
•   HP Smart Array Controllers 
•   HP StorageWorks Disk arrays 
•   Device Mapper multipath solution 
•   HP ProLiant servers 
•   HP ProLiant Gigabit Ethernet  Multifunction server adapter 
 
Introduction 
Traditionally, servers were configured to install th e operating system on internal direct attached 
storage device (local disk). With advances in st orage technologies, and the need for storage and 
server consolidation, there is a need to enabl e booting from the Storage Area Network (SAN) 
and providing high availability fe atures for the operating system. 
 
The high availability feature for the Boot device on SAN during the boot process is provided by 
configuring the HBA BIOS with re dundant boot paths. Many vendors refer to this feature as Boot 
from SAN (BFS). For more information, see  Configuring Boot from SAN
. 
 
Linux operating system vendors have incorporated the multipathing feature for the operating 
system installation partitions. For more information, see  Installing the operating system
. 
 
Supported Configuration 
Device Mapper Multipath supports Bo ot-from-SAN operations on ProLiant and HP Integrity servers. 
This functionality is specifically HBA/BIOS ce ntric. For BFS-supported HP StorageWorks disk 
arrays and HBAs, see Single Point of  Connectivity Knowledge (SPOCK) at: 
http://www.hp.com/storage/spock
. You must sign up for a HP Passport to enable access. 
 
High availability on installation partitions is  supported by the following operating systems: 
 
•   Red Hat distribution - RHEL 5 Update 2 and above 
•   Novell distribution - SLES 10 SP2 and above 
           SLES 11 and above 
 
Note : It is recommend to have separate device s for the /boot and root (/) partitions. 
Enabling multipath features for the Installation  partitions on SAN with HP Smart Array p700m 
controller is supported only on SLES 10 SP2/SL ES 11 operating system and above. Refer to the 
product release documents for latest updates.  
						

							 
Configuring boot from SAN 
Boot from SAN has become a de facto description for the capability of having a server boot its 
operating system from SAN. The HBA ROM provides  this functionality. Once HBAs are configured 
to boot from the disk device on the SAN, th e server boots as if it were a local disk.  
 
More than one HBA can be configured for the redu ndant boot path for the High Availability of the 
Boot device. The Failover feature during boot time is provided by the HBA ROM configuration. 
 
Note:  Device Mapper Multipathing fe atures are available after the kernel loads the multipathing 
modules from the initial RAM disk image. 
 
Configuring the HBA/NIC ROM for Hi gh Availability of Boot device 
To set up your Linux server to boot from  a SAN device, complete the following steps: 
 
Setting up the storage arrays 
1.  Create two Logical units for Boot and Root devices 
2.  Present the Logical units to the Linux server 
 
Note:  For more information on configuring the Logical units, refer to the HP StorageWorks array 
User Guide. 
 
Setting up the host systems 
To configure the host boot order for HP ProLiant  servers with Multifunctional Gigabit Ethernet 
Server Adapter, complete  the following steps: 
1.  While the system is booting, press F9 to start the BIOS Setup Utility.  
2.  Select Boot Controller Order.  
1.  Select the HBA configured to provide the boot  device and move it to Controller Order 1.  
2.  In case of multiple HBAs, set to  the higher Controller Order. 
3.  Press Escape, and press F10 to save your  configuration and exit the utility.  
 
To enable the iSCSI boot option ROM for HP ProLiant Gigabit Ethernet Multifunction server 
adapter in your server, comple te the following steps:  
 
1.  While the system is booting, press F9 to start the BIOS Setup Utility.  
2.  Select  System Options . 
 
Figure 1 
 
 
a.  Select  Embedded NICs .  
						

							 
Figure 2 
  b.  Select the NIC to which the boot option  is to be set and press Enter twice. 
 
Figure 3 
 
c.   Select  iSCSI Boot  and press Enter. 
 
Figure 4 
 
d.   iSCSI Boot must be displayed as the  boot option for the NIC you selected. 
 
Figure 5  
						

							 
3. Press Escape, and then press F10 to save  your configuration and exit the utility. 
 
Configuring HBA/NIC ROM 
This section details the steps to configure  the Host Bus Adapter to boot from SAN. 
Qlogic HBA ROM configuration
 
Emulex HBA ROM configuration
 
HP Smart Array P700m Controller ORCA configuration
 
HP SC08Ge SAS HBA configuration
 
HP ProLiant Gigabit Ethernet Multif unction server adapter configuration
  
						

							Qlogic HBA ROM configuration 
 
To configure the boot device for high availability on HP ProLiant servers, complete the following 
steps: 
 
1.  While the server is booting, press Ctrl+Q to enter  Fast!UTIL.  
2.  From the  Select Host Adapter  menu, select the HBA you want to boot, and press Enter. 
 
Figure 6  
 
3.  From the  Fast!UTIL Options  menu, select Configuration Settings , and press Enter. 
 
Figure 7  
  
						

							4. From the  Configuration Settings  menu, select Adapter Settings , and press Enter. 
 
Figure 8  
 
5.  From the  Adapter Settings  menu, change Host Adapter BIOS to  Enabled by pressing Enter. 
 
Figure 9  
 
6.  Press ESC to go back to the  Configuration Settings menu Figure 8
. 
7.  Select  Selectable Boot Settings , and then press Enter.  
8.  From the  Selectable Boot Settings  menu, enable the Selectable Boot option by pressing Enter, 
move the cursor to Primary Boot Port Name, LUN, and press Enter. 
 
Figure 10 
  
						

							9. From the  Select Fibre Channel Device  menu, select the controller Port Name of the array and 
press Enter. 
 
Figure 11  
 
10.  From  Select LUN  menu, select the device to  boot from, and press Enter. 
 
Figure 12  
 
Note:  LUN index in the previous figure corresponds to the Lun ID of the boot device 
presented to the host. 
 
11.  From the  Selectable Boot Settings  menu, to configure the secondary boot paths, select Boot 
Port Name, Lun. Repeat Step 8 and Step 9 for  all the other controller ports of the array.   
						

							 
Figure 13  
 
12.  Save the changes by pressing ESC twice, and  then select Save Changes. This saves the 
configuration changes to selected HBA.  
13.  From the  Fast!UTIL Options  menu, choose Select Host Adaptor  option, and press Enter. Select 
the other HBAs ( Figure 6
) and repeat the steps 2 to 12 to configure the HBA for booting the 
server. 
 
Note:  Refer to the “Booting Itanium Linux systems fr om a storage area network application notes” 
for the procedure to configure the HBA ROM on an Itanium server. You can locate this guide in 
the SPOCK website ( http://www.hp.com/storage/spock
) under Boot Guide Application Notes. 
You must sign up for a HP Passport to enable access. 
  
						

							Emulex HBA ROM configuration 
 
To configure the boot device for high availability on HP ProLiant servers, complete the following 
steps: 
1.  While the server is booting, press Alt+ E when the following message appears:  
     Press  To Go To Emulex BIOS Utility .  
2.  The Emulex BIOS utility displays  Emulex Adapters  in the system. At the  Enter a Selection 
prompt, select the HBA index number. 
 
Figure 14  
 
3.  From the HBA  configuration menu  screen, select option 2, Configure This Adapter’s 
Parameters. 
 
Figure 15 
 
4.  From  Configure Adapter’s Parameters  screen, select option 1, Enable or Disable BIOS. Press 
1 to enable the BIOS; press Esc to return to the main menu.