Installation guide

Chapter 2. Hardware Installation and Operating System Configuration 25
2.4.2. Decreasing the Kernel Boot Timeout Limit
It is possible to reduce the boot time for a node by decreasing the kernel boot timeout limit.
During the Red Hat Enterprise Linux boot sequence, the boot loader allows for specifying
an alternate kernel to boot. The default timeout limit for specifying a kernel is ten seconds.
To modify the kernel boot timeout limit for a node, edit the appropriate files as follows:
When using the GRUB boot loader, the timeout parameter in /boot/grub/grub.conf
should be modified to specify the appropriate number of seconds for the timeout param-
eter. To set this interval to 3 seconds, edit the parameter to the following:
timeout = 3
When using the LILO or ELILO boot loaders, edit the /etc/lilo.conf file (on x86
systems) or the elilo.conf file (on Itanium systems) and specify the desired value (in
tenths of a second) for the timeout parameter. The following example sets the timeout
limit to three seconds:
timeout = 30
To apply any changes made to the /etc/lilo.conf file, invoke the /sbin/lilo com-
mand.
On an Itanium system, to apply any changes made to the
/boot/efi/efi/redhat/elilo.conf file, invoke the /sbin/elilo command.
2.4.3. Displaying Console Startup Messages
Use the dmesg command to display the console startup messages. Refer to the dmesg(8)
man page for more information.
The following example of output from the dmesg command shows that two external SCSI
buses and nine disks were detected on the node. (Lines with backslashes display as one
line on most screens):
May 22 14:02:10 storage3 kernel: scsi0 : Adaptec AHA274x/284x/294x \
(EISA/VLB/PCI-Fast SCSI) 5.1.28/3.2.4
May 22 14:02:10 storage3 kernel:
May 22 14:02:10 storage3 kernel: scsi1 : Adaptec AHA274x/284x/294x \
(EISA/VLB/PCI-Fast SCSI) 5.1.28/3.2.4
May 22 14:02:10 storage3 kernel:
May 22 14:02:10 storage3 kernel: scsi : 2 hosts.
May 22 14:02:11 storage3 kernel: Vendor: SEAGATE Model: ST39236LW Rev: 0004
May 22 14:02:11 storage3 kernel: Detected scsi disk sda at scsi0, channel 0, id 0, lun 0
May 22 14:02:11 storage3 kernel: Vendor: SEAGATE Model: ST318203LC Rev: 0001
May 22 14:02:11 storage3 kernel: Detected scsi disk sdb at scsi1, channel 0, id 0, lun 0
May 22 14:02:11 storage3 kernel: Vendor: SEAGATE Model: ST318203LC Rev: 0001
May 22 14:02:11 storage3 kernel: Detected scsi disk sdc at scsi1, channel 0, id 1, lun 0