Installation guide

Chapter 20. Additional Boot Options
This section discusses additional boot and kernel boot options available for the Red Hat Enterprise
Linux installation program.
To use any of the boot options presented here, type the command you wish to invoke at the
installation boot: prompt.
You can also store kernel boot options for the z/IPL boot loader in the zipl.conf file, either by
editing the file manually or using the z ip l tool.
Kernel parameters in zipl.conf that contain quotation marks
Where kernel parameters use nested quotation marks, the required order in Red Hat Enterprise
Linux is double quote marks for the outer set and single quote marks for the inner set. For
example, parameters="vmhalt='LOGOFF'" is correct, while
parameters='vmhalt="LOGOFF"' is not correct and may lead to unexpected behavior.
b o ot t ime co mman d arg u men t s
askmethod
this command asks you to select the installation method you would like to use when
booting from the Red Hat Enterprise Linux CD-ROM.
dd=url
this argument causes the installation program to prompt you to use a driver image from a
specified HTTP, FTP, or NFS network address.
display=ip:0
this command allows remote display forwarding. In this command, ip should be replaced
with the IP address of the system on which you want the display to appear.
On the system you want the display to appear on, you must execute the command xhost
+remotehostname, where remotehostname is the name of the host from which you are
running the original display. Using the command xhost +remotehostname limits access
to the remote display terminal and does not allow access from anyone or any system not
specifically authorized for remote access.
mediacheck
this command gives you the option of testing the integrity of the install source (if an ISO-
based method). this command works with the CD, DVD, hard drive ISO, and NFS ISO
installation methods. Verifying that the ISO images are intact before you attempt an
installation helps to avoid problems that are often encountered during an installation.
mpath
enables multipath support.
⁠Chapt er 2 0 . Addit ional Boot O pt ions
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