HP Unix和Linux启动过程对比

Linux-x86引导过程：   BIOS->设备主MBR->引导程序（grub/lilo）->加载Kernel->系统init->rc

HP Unix-PA Risk引导过程：PDC->LIF->ISL(prim)->HPUX(second)->加载Kernel->系统init->rc

PDC:

Processor Dependent Code,写在CPU的RAM当中，即为firmware，在进行下一步引导前，硬件方面的工作和主、次引导设备的选择都是由它来完成的。--non-volatile。

系统引导时当提示：Press any key within 10 seconds to interrupt时，按任意键进入PDC.

To discontinue, press any key within 10 seconds.

Boot terminated.
---- Main Menu ---------------------------------------------------------------
Command Description
------- -----------
BOot [PRI|ALT|] Boot from specified path
PAth [PRI|ALT] [] Display or modify a path
SEArch [DIsplay|IPL] [] Search for boot devices
COnfiguration menu Displays or sets boot values
INformation menu Displays hardware information
SERvice menu Displays service commands
DIsplay Redisplay the current menu
HElp [|] Display help for menu or command
RESET Restart the system
----
Main Menu: Enter command or menu >

 

ISL: PDC在指定的设备上查找LIF头，因为LIF头包含了引导信息和ISL引导程序。

系统启动后可以用如下方式看到ISL信息：

# lifls -l /dev/rdsk/c1t6d0
volume ISL10 data size 7984 directory size 8
filename type start size implement created
===============================================================
ISL -12800 584 306 0 00/11/08 20:49:59
HPUX -12928 896 848 0 00/11/08 20:50:00
LABEL BIN 1744 8 0 01/05/31 06:54:08
AUTO -12289 1752 1 0 01/05/31 06:54:10

 

hpux：常被称为二级引导程序。用来加载kernel--vmunix

ISL> lsa
Auto-execute file contains:
hpux

 

用hpux引导kernel的时候可以指定kernel的路径，并同时给kernel传递内核参数。可以使系统启动并进入单用户模式或维护模式：

hpux (;

)

simply using hpux is equal to:
hpux (;0)/stand/vmunix

 

Options:

-is single user mode boot
    Activate vg00, mount only / and /stand, do not go through the startup script.
So e.g. the network is not started and other users cannot login.

-lq quorum mode boot
    Same as single user mode but the root VG (vg00) gets activated even if the LVM
quorum is not present, i.e only 50% or less of the disks are available. This option
can be used if a mirrored root disk is defect.
-lm maintenance mode boot
    vg00 will not be activated. The root FS is mounted using the auxiliary device file
/dev/root. In this mode you are able to export vg00 and perform LVM low level troubleshooting.

 

In order to boot without quorum check into single user mode type:
ISL> hpux -is -lq

 

ISL> hpux ll

Shows the content of the boot filesystem /stand.

In the next steps the kernel initializes memory, IO and forks off /sbin/pre_init_rc

and mount root file system read-write afterwards.

 

INIT: /etc/inittab

 

Console Login: