IBM System storage DS6000 Series, Attachment Manual

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/dev/vpatha3, enter
/bin/mount -o rw -t ext3
, or
/dev/vpatha3 /sysroot
,
or for a reiserfs root file system on /dev/vpatha3, enter /bin/mount -o rw
-t reiserfs /dev/vpatha3 /sysroot
To copy the dynamically created device special files onto the systems root
file system, enter the following commands:
tar cps /dev/IBMsdd /dev/vpath* | (cd /sysroot && tar xps)
/bin/umount /sysroot
You must define the root file system to the kernel. Traditionally, this
information is passed to the bootloader as a string, for example
/dev/vpatha3 and translated to a hexadecimal representation of the major
and the minor numbers of the device. If the major and minor numbers
equals 254,3, these numbers are represented in hex as 0xFE03. The
linuxrc script passes the hexadecimal value into /proc with the following
commands:
echo 0xFE03 > /proc/sys/kernel/real-root-dev
/bin/umount /proc
18. Edit the system fstab and change all the system mount points from LABEL or
/dev/sd mount sources to their equivalent /dev/vpath . Refer to step 23 for
dangers of booting by label in a multipath configuration.
19. Copy the system fstab to the initrd etc/ directory.
20. Unmount the image and remove the loopback binding by typing the following
commands:
umount /mnt/tmp
losetup -d /dev/loop0
21. Compress the image by typing the following commands:
gzip -9 _initrd_file_
mv _initrd_file_.gz _initrd_file_
22. Append the following to your boot parameters (for example, in lilo.conf,
grub.conf, or menu.lst):
ramdisk_size=34000
If you created a larger initrd file system, make this value large enough to cover
the size.
23. For completeness, change the bootloader append for the root parameter of the
kernel to the appropriate vpath device. For example, root=/dev/vpatha5 .
However, the previous steps override this value by passing the corresponding
hex major, minor into the /proc file system within the initrd linuxrc script.
Note: If you boot by LABEL, there is a risk that the first device that is found in
the fabric with the correct label could be the wrong device or that it is
an sd single-pathed device instead of a vpath multipathed device.
24. Reboot the server. It will boot with the root file system on a vpath device
instead of on an sd device.
Figure 62 on page 121 and Figure 63 on page 122 illustrate a complete linuxrc file
for Red Hat and for SUSE.
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DS6000 Host Systems Attachment Guide