Creating a custom Red Hat installation DVD

Created on 19^th October 2005 How to create a single CD for fast and easy customized installation. Setting up the build directory: The first thing to do is to copy all the cdrom ISOs to one location: mkdir -p /mnt/disk{1,2,3,4} mount -o loop RHEL4-U1-i386-AS-disc1.iso /mnt/disk1 mount -o loop RHEL4-U1-i386-AS-disc2.iso /mnt/disk2 mount -o loop RHEL4-U1-i386-AS-disc3.iso /mnt/disk3 mount -o loop RHEL4-U1-i386-AS-disc4.iso /mnt/disk4 We now copy all the files from the directories to a single directory: mkdir -p /data/isobuild rsync -rv /mnt/disk{4,3,2,1}/* /data/isobuild/ We also need to copy across the .diskinfo file that is not caught by our *: cp /mnt/disk1/.diskinfo /data/isobuild/ The .diskinfo file identifies the CD as being a correct Red Hat Installer disk and is checked by anaconda during the start of the install. We could now build the DVD as it is but we really should have a fiddle first :-) Adding more software to the DVD We could add some of our own rpms to /data/isobuild/RedHat/RPMS; however by just doing this does not make them available at install time. There is an XML file that is read and ensures that the packages are installed in the correct order. So let us throw a few random packages into the mix: Add some java: cp jre-1_5_0_03-linux-i586.rpm /data/isobuild/RedHat/RPMS/ Some encryption for GAIM: cp gaim-encryption-2.36-3.rf.i386.rpm /data/isobuild/RedHat/RPMS/ Updating the comps.xml file We need to ensure that the host computer has anaconda and anaconda-runtime installed: up2date anaconda anaconda-runtime Before we update the XML dependency file we need to sort out package orders. If you have added a lot of new packages you may need to remove some old packages that you have replaced with newer versions to stop conflicts. So the first command is: PYTHONPATH=/usr/lib/anaconda /usr/lib/anaconda-runtime/pkgorder \ /data/isobuild/ i386 > /data/isobuild/xander-pkgorder This creates a list of files in the order it needs to install them in the file /data/isobuild/xander-pkgorder. Sometimes an occasional RPM will not provide the information anaconda needs. You can edit the file manually and insert your RPMs at the end. Next we need to generate the dependency file: /usr/lib/anaconda-runtime/genhdlist --fileorder /data/isobuild/xander-pkgorder \ /data/isobuild/ You will probably have a few hiccoughs the first time you run these commands. Most may be resolved by adding the missing entries to the pkgorder file or deleting duplicate packages. Creating an automated installer We could *now* if we wanted to build our DVD; however we can make an automated installer. So crack open system-config-kickstart and create a kickstart file with all the packages and partitioning etc you need for your systems. copy the resulting file to /data/isobuild/ks.cfg we can now edit the file /data/isobuild/isolinux/isolinux.cfg copy or change the three lines: label linux kernel vmlinuz append initrd=initrd.img ramdisk_size=8192 to label xander kernel vmlinuz append initrd=initrd.img ramdisk_size=8192 ks=cdrom:/ks.cfg Then change the default at the top of the file to xander. This means that the default action is to install directly from the DVD using your kickstart file. Building the DVD iso Now to build the iso: cd /data/isobuild chmod a+w isolinux/isolinux.bin mkisofs -r -T -J -V "Custom RHEL4 Build" -b isolinux/isolinux.bin \ -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 \ -boot-info-table -o /data/custom-RHEL4-dvd.iso /data/isobuild/ Buring the DVD Now we can burn the image to the CD. I assume the CD writer is already set up on your system. We use cdrecord below, but you can use other programs as well. The command is invoked as: cdrecord -v speed=4 dev=0,0,0 /data/custom-RHEL4-dvd.iso The speed and dev options depend on your system. The device for the dev argument can be determined by using the -scanbus option to cdrecord: cdrecord -scanbus Using the DVD Once the image is burned onto the DVD, insert the DVD into the target machine and boot the machine. You should get the custom message that you created earlier. At this point, you can either press Enter at the boot prompt or let it timeout. When it times out it uses the default label, which we specified as ks (Kickstart).