Upgrade Linux system with Kickstart of RedHat

Article Title: Upgrade the Linux System Using Kickstart of RedHat. Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source.

This article briefly introduces how to use Kickstart and network installation functions of Red Hat Linux to quickly upgrade your Linux system. The example in this article is to remotely upgrade from Red Hat 7.2 to Red Hat 9.0.

Since version 5.2, Red Hat Linux has added a feature called Kickstart, mainly to reduce the interactive system parameter input during installation and improve installation efficiency. It is especially suitable for applications that require quick installation of hundreds of Linux workstations in a short time. Menlo Park at Stanford University has a wonderful article.

　　1. System check before Upgrade

Before upgrading the system, some problems that are easy to ignore may interrupt the Kickstart process. These problems are generally because the system configuration does not meet the minimum installation requirements, therefore, it is best to perform a full test before the automatic upgrade. Since the development of Red Hat Linux, it has not been as smooth as 386 (Red Hat 9 cannot run on machines smaller than 586 ), therefore, it is necessary to fully check the system before the upgrade, including the following:

Whether the storage space is sufficient. Red Hat 9 requires at least 32 MB of memory and MB of hard disk. The memory is generally not a problem, but I failed to install the system on a MB hard disk, of course, the hard disks are still relatively large and can be fully installed. Linux system files are mainly stored in/usr, and some of the files below/. Generally, if the X system and large software are not installed, /usr can work well with 1 GB space and MB space. My system is upgraded from 7.2 to 9.0, and the usage of/usr and/is about 30% more than before the upgrade, therefore, if your/usr and/usage are not too high, the disk space limit is generally not a problem.

Whether the swap partition space is sufficient. A hard-to-find difference between Red Hat 9 and 7.2 Is that 7.2 of the system can use swap partitions with less than twice the physical memory capacity, two or more times of physical memory swap partitions are recommended, while Red Hat 9 must use two or more times of physical memory swap partitions, therefore, if your Linux system only has less than two times of swap partitions, you can only divide one swap partition or add another swap file, you can also dial your memory to make the system swap partition more than twice the physical memory. I suggest adding a swap partition, and adding swap files cannot be implemented in Kickstart, as for allocating the memory, there is no way to dial the memory for remote upgrade.

Miscellaneous. The system will detect a series of hardware during the automatic upgrade process. If you select graphical interface for installation, but there is no mouse, the system will prompt you to use text for installation; or the system does not support graphical interface installation if the memory size is 32 MB. You can modify these settings in the Automatic Installation configuration file to prevent them from occurring, however, recording down all the hardware configurations of the system to make a list will be of great help to make an automatic configuration file.

　　2. How to start the installer

Start with the installation program started in Red Hat Linux. From the official installation and installation manual of Red Hat Linux, we can see several main startup Methods: CDROM, soft drive, and dosutils \ autoboot running on the CD from the dos environment. bat files in three ways, for us this is still not enough, our Linux workstation is not a soft drive and optical drive, of course, there is no dos. Analyze the boot * in the/images directory of the first disc of each release *. the img file shows that there are only two main startup image files: vmlinuz kernel and initrd. img, initrd. img is a compressed file system. Extract these two files to the existing Linux/boot directory, and add the corresponding configuration lines to the system bootloader (usually LILO or GRUB) configuration file to start the installation program. Take Red Hat 7.2 and GRUB for example (use the network of Red Hat 8.0 to start the image file ):

[root@client mnt]# mount -o loop -o ro /mnt/nfs/psyche/cd1/images/bootnet.img bootnet 　　[root@client mnt]# cd bootnet/ 　　[root@client bootnet]# ls 　　boot.msg initrd.img options.msgrescue.msgsplash.lsssysLinux.png 　　general.msgldLinux.sysparam.msgsnake.msgsysLinux.cfgvmlinuz 　　[root@client bootnet]# cp vmlinuz /boot/vmlinuz8 　　[root@client bootnet]# cp initrd.img /boot/initrd8 　　[root@client bootnet]# vi /boot/grub/menu.lst

Add the following three rows:

title Upgrade to Psyche via NFS 　　kernel /boot/vmlinuz8 ro 　　initrd /boot/initrd8

Note: There is no configuration for the/boot partition. If there is a/boot partition, the previous/boot is not required. See the NOTICE section in the GRUB configuration file.

After restarting, you can select a network upgrade. The effect is the same as that of booting the system with a bootnet floppy disk. Here, we will use another Startup File of Red Hat 9, which is also the boot. iso file that appears only recently in the Red Hat release. After loading the ISO image file of the first CD of Red Hat 9 release, we found that the images directory under it has a boot larger than the 7 Series release. iso file (the first CD root directory in 8.0 also contains a similar directory). After loading the file, it is found that it contains a large kernel and initrd file, the initrd contains a hardware driver that is often used to install the system. When started using this file, I can automatically identify the video card of the PM133 board and the rarely seen adaptec ANA-6911TX card (starfire. o), so we strongly recommend that you use boot. automatic iso upgrade saves the trouble of driving. It is worth mentioning that Red Hat 9 is no longer in boot. img has its own NIC Driver, while Red Hat 8 is in bootnet. img drivers with some common NICs (intel 55X series, tulip, 8139, etc.), decompress bootnet. initrd. the img file can be seen in the lib directory.

 

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