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10.5. Alternative System Install Methods Figure 26.2. The Rawwrite Program Select the boot image to be copied and the target device. In almost every case, the target device is the A: drive (the first floppy disk drive). Then insert an empty disk into your chosen floppy drive and click on the Write button. When completed click on Exit : you now have a floppy boot disk to install your Mandriva Linux distribution. 10.5.2. Creating a Floppy Boot Disk From GNU/Linux If GNU/Linux is already installed on your machine (another version on another machine, etc.), carry out the following steps: 1. Mount the CD-ROM, if needed. Let’s suppose that the mount point is /mnt/cdrom. 2. Log in as root (to do so, open a terminal window, run the su command and enter root’s password). 3. Insert an empty diskette into the floppy drive and type: $ dd if=/mnt/cdrom/install/images/cdrom.img of=/dev/fd0 bs=512

10.5. Alternative System Install Methods ext2FS, ext3FS or ReiserFS partition). On the hd_grub customization site [http: //qa.mandriva.com/hd_grub.cgi] you will find a little tool which may prove helpful to customize your boot floppy. all.img This image contains all of the boot floppy images above, and more. If your machine supports booting from USB, you can transfer this image to a USB key and boot the installation from it. Transferring the all.img to a USB key will erase all of the USB key contents. Back up first, and use with care. 10.5.1. Creating a Boot Disk With Windows To do so, use the rawwrite program. You will find it in the CD-ROM’s dosutils/ directory. You may have noticed that there is a DOS version of the same program called rawrite. In fact, this is the original version of the program. rawwrite is a graphical front-end to it. Start the program as shown in Figure 26.2, The Rawwrite Program [374].

10.4. My Computer is slow linmodems.org/] and the Winmodems are not modems [http://start.at/modem/] web sites. 10.4. My Computer is slow If you notice your computer is really slow, or significantly slower than with other GNU/Linux versions, you might overcome this problem by disabling ACPI support. To do so, add the following to your /etc/lilo.conf file: append=”acpi=off” If the file already has an append= line, only add acpi=off at its end. Running lilo -v as root and rebooting your computer will make the changes effective. 10.5. Alternative System Install Methods You might need to install your Mandriva Linux system using an alternative installation method, for example over the network, or from external storage devices. You will need an alternative floppy boot disk. The CD-ROM contains all of the image files and utility programs needed to create a floppy boot disk. The floppy boot disk images are in the CD-ROM’s /install/images directory. The following is a list of different images and their respective installation methods: cdrom.img To install from a local IDE or SCSI CD-ROM drive. network.img and network_drivers.img To install from an NFS, FTP, HTTP repository on your local LAN or from one via the Internet. The network configuration of the machine on which you wish to install may be manual or automatic. Please make sure that you make both floppies. pcmcia.img Use this image if the installation medium is reached through a PCMCIA card (network, CD-ROM, etc.). Some PCMCIA devices use common network drivers. If the PCMCIA device does not work, try again with network.img and net work_drivers.img. hd_grub.img Use this image if you want to perform the installation from a hard disk. You need to copy the contents of the CD onto the hard drive (either on a FAT,

10.1. Legacy-Free Systems 10.1. Legacy-Free Systems Hardware manufacturers have recently introduced what they call legacy-free 3 systems , mainly on laptops, but there are also legacy-free desktop computers. This basically means that the BIOS has been considerably reduced to allow you only to choose which media to boot from. Mandriva Linux will be able to configure everything properly. 10.2. nVidia and ATI 3D Graphics Cards Computers with nVidia or ATI graphics cards need a patched kernel to be able to use OpenGL hardware 3D acceleration on OpenGL-compatible applications. If you own a Mandriva Linux PowerPack Edition , the kernel should have been installed by DrakX. If this is not your case, please obtain and install the corresponding packages. You can visit nVidia’s web site [http://www.nvidia.com] and ATI’s web site [http://www.ati.com] and download the appropriate drivers, or you can download the RPM packages from Mandriva Club [http://club.mandriva.com]. Then run Mandriva Linux Control Center and re-configure X from there. 10.3. Winmodems winmodems are also called controller-less modems or software modems. Support for these peripherals is improving. Drivers do exist, but most of them are in binary form and available only for newer kernel versions. If you have a PCI modem, look at the output of cat /proc/pci run as the root user from a terminal window. It tells you the device’s I/O port and IRQ. Then use the setserial command (for our example, the I/O address is 0xb400, the IRQ is 10and th the modem is the 4 serial device) as follows: setserial /dev/ttyS3 port 0xb400 irq 10 UART 16550A Then try to query your modem using minicom or kppp. If it doesn’t work, you may have a software modem. If it does work, create the /etc/rc.d/rc.setserial file and place the appropriate setserial command line in it. If you happen to have a software modem in your machine, and you have a Mandriva Club account, you might find an RPM package that supports your modem (try searching on the ltmodem package for instance). You should also take a look at the web site of your modem’s manufacturer and at the linmodems [http:// Refer to the great Linux on Laptops [http://www.linux-laptop.net] web site for more information on your laptop make/model.

9.1. From the Console kill command to terminate it, or you can use the xkill tool or other graphical tools such as the ones that show the process tree. 9.1. From the Console The first thing to do to terminate a misbehaving program is to find its PID, or process ID. To do so, execute the following from a console: ps aux | grep mozillafirefox-bin, supposing that Firefox is the misbehaving program. You will get something like the following, which tells you among other things that Firefox was started by user peter and that its PID is 3505: peter 3505 1.7 5.0 82208 25804 ? Sl 09:30 0:01 . /usr/lib/mozilla-firefox-1.0.6/mozilla-firefox-bin Now that we have the PID of the misbehaving program, we can execute the kill command to terminate it. So we execute the following: kill -9 3505, and that’s it! Firefox is killed. Note that this is only to be used when the program doesn’t respond to your input anymore. Do not use it as a standard means of exiting from applications. Actually, we sent the KILL signal to the process number 3505. The kill command accepts other signals besides KILL, so you can have greater control over your processes. For more info, see kill(1), as well as Chapter 36, Process Control [487]. 9.2. Using Graphical Monitoring Tools You can also use the graphical process’ status tools (such as KPM, KSySGuard, and GTOP to name a few) which allow you to point to the process name and with one click send that process a signal or just kill that process. If you are using KDE, you can press the Ctrl Alt -Esc keys: the pointer changes to a skull with crossed bones and you can simply click on the window of the misbehaving application to kill it. 10. Miscellaneous Some considerations on newer hardware such as legacy-free systems, nVidia and ATI 3D graphics accelerator cards, winmodems and other things that don’t fit in the preceding sections.

9. Killing Misbehaving Apps 4. If the system doesn’t respond to any of these steps, you have to go through the SysRq (System Request) sequence. The SysRq sequence involves pressing and holding three keys at once: the left Alt key, the SysRq key (labeled Print Screen on older keyboards) and a letter key. SysRq -R puts the keyboard in raw mode. Now try pressing Ctrl -Backspace again to kill X. If that doesn’t work, carry on. a. Alt - Alt - b. Alt -SysRq - S attempts to write all unsaved data to disk ( sync the disk). c. Alt -SysRq - E sends a termination signal to all processes, except for init. d. Alt -SysRq - I sends a kill signal to all processes, except for init. e. Alt -SysRq - U attempts to re-mount all mounted filesystems read-only. This removes the dirty flag and prevents a filesystem check upon reboot. f. Alt -SysRq - B reboots the system. You might just as well press the reset button on your machine. Remember that this is a sequence, i.e. you have to press one combination after the other in the right order: Raw, Sync, tErm, kIll, Umount, 2 reBoot. Read the kernel documentation for more information on this feature. 5. If none of the above helps, cross your fingers and press the reset switch on your machine. If you are lucky, GNU/Linux will just run a disk check upon reboot. By all means, try to find out what causes these lockups because they can do severe damage to the filesystem. You might also want to consider using one of the journaling filesystems included in Mandriva Linux: ext3, reiserfs, etc. which handle such failures more gracefully. However, replacing ext2FS with reiserfs requires reformatting your partitions. You can use tune2fs -j /dev/hdaN to convert the th filesystem in the N partition of the first IDE disk from ext2FS to ext3FS. 9. Killing Misbehaving Apps Well, this one is not so hard after all. You have many ways to do it. You can do it by finding the PID of the program which stopped responding, and then using the Mnemonic phrase: Raising Skinny Elephants Is Utterly Boring

8. Recovering from a System Freeze One recovery tool is Recover. It’s an interactive tool. You can find it in the contribs CD-ROM or on the Rpmfind web site [http://www.rpmfind.net]. Once you have the RPM, install it. Then run it with recover and answer the questions it asks you. The questions help you to set a time span to look for deleted files and directories 1 to minimize the time it takes to do the search. Once the tool finishes its search, it asks you where you want to save the recovered files and directories. Pick a directory of your choice, and you have all the files and directories recovered into it. Note that you won’t be able to recover the file names, just their contents, but you can inspect them or try to rename them with different names until you get the right one. This is better than nothing. There are also mini-HOWTOs related to undeletion for ext2, look at Ext2fs- Undeletion [http://www.tldp.org/HOWTO/mini/Ext2fs-Undeletion. html] and undeletion of whole directory structures [http://www.tldp. org/HOWTO/mini/Ext2fs-Undeletion-Dir-Struct/index.html]. 8. Recovering from a System Freeze When stuck in a freeze , your computer doesn’t respond to commands anymore and input devices such as keyboard and mouse seem to be blocked. This is a worst- case scenario and could mean that you have a very severe error in either your configuration, your software or your hardware. We will show you how to deal with this annoying situation. In the case of a system freeze, your top priority should be trying to shutdown your system properly. We assume you are running under X. So try these steps consecutively: 1. Try to kill the X server by pressing the Ctrl -Alt -Backspace keys. 2. Try to switch to another console by pressing the Ctrl Alt Fn keys (where n — is the console number, from 1 to 6). If you succeed, login as root and issue the command: kill -15 $(pidof X) or the command kill -9 $(pidof X), if the first command shows no effect. Check with top to see if X is still running. 3. If you are part of a local network, try to use ssh to connect into your machine from another. It is advisable to ssh into the remote machine as an unprivileged user and then use the su command to become root. You can search for all deleted files too by appending the -a option, but it takes much longer…

7. Filesystem Issues 7. Filesystem Issues 7.1. Repairing a Damaged Superblock The information below only applies to ext2 and ext3 filesystems. If you use a different filesystem, please check its documentation. The superblock is the first block of each ext2FS/ext3FS partition. It contains important data about the file system, such as its size, free space, etc. (it is similar to the method used by FAT partitions). A partition with a damaged superblock cannot be mounted. Fortunately, ext2FS/ext3FS keeps several superblock backup copies scattered over the partition. Boot your system with a boot disk. The backup copies’ location depends on the block size of the filesystem. For filesystems with 1 KB block sizes it is at the beginning of each 8 KB (8192 bytes) block. For filesystems with 2 KB sizes it is at the beginning of each 16 KB (16384 bytes) block, and so on. You can use the mke2fs n [your_disk_device_name] command to find out at which byte positions the superblock copies are. Assuming a 1 KB block size, the first backup copy is in byte number 8193. To restore the superblock from this copy, execute e2fsck -b 8193 /dev/hda4; change hda4 accordingly to reflect the name of your damaged partition. If that block also happens to be damaged, try the next one at byte number 16385, and so on until you find a suitable one. Reboot your system to activate the changes. 7.2. Recovering Deleted Files We discuss ways of recovering deleted files and directories. Please bear in mind that recovery tools are not magical, and they will only work depending on how recently you deleted the file(s) you are trying to recover. You might be wondering how to recover files you accidentally deleted. There are some utilities designed for GNU/Linux’s ext2 filesystem which allow you to recover deleted files and directories. However they won’t recover the files you deleted a few months ago because of disk usage, space marked as free will have been overwritten. So the best way to protect against accidental or not so accidental deletions is by making backups. There are not (as yet) tools to recover files deleted on reiserfs file systems. Keep in touch with the ReiserFS home page [http://www.namesys.com] for the latest news about it.

6.2. Backing Up and Restoring the MBR 6.1.2. With GRUB If you use GRUB things are a little bit different to that of LILO. In the following example we assume that you are trying to install GRUB in the MBR of your first IDE drive, and that the file stage1 is in the /boot/grub/ directory. First, invoke GRUB’s shell by issuing the grub command. Once there, issue the following command: root (hd0,0). This will tell GRUB that the files it needs are in the first partition (0) of your first hard disk (hd0). Then issue the following command: setup (hd0). This installs GRUB in the MBR of your first hard disk. That’s it! You can also try to use grub-install /dev/hda to install GRUB on your first hard drive’s MBR, but the method described above is the preferred one. 6.1.3. Some Considerations for Dual-Booting Systems Windows 9x, NT, 2000 and XP upgrades. If you run a dual-boot system, be very careful to always have a GNU/Linux boot disk prepared. If you don’t have a boot disk, and you (re)install Windows (all versions) you won’t be able to boot GNU/Linux after the Windows upgrade because Windows rewrites the MBR without any warning at all. 6.2. Backing Up and Restoring the MBR To make a backup copy of your hard disk’s MBR, insert a blank floppy in your floppy disk drive and issue the following: # dd if=/dev/hda of=/dev/fd0/mbr.bin bs=512 count=1 If you want to restore a backed up copy of your hard disk’s MBR, insert the floppy containing it into your floppy disk drive and issue the following: # dd if=/dev/fd0/mbr.bin of=/dev/hda bs=512 The above examples assume that the MBR of your first IDE hard disk (/dev/hda) is backed up to a file named mbr.bin on your first floppy diskette drive (/dev/fd0) and should be run as the root user.

6. Bootloader Issues you have to define that run level on the boot prompt. Under LILO, press the Esc key once and type linux init 3. Under GRUB, press the E key twice, add init 3, press the Enter key and then the B key to boot. For a more detailed description about run levels, please refer to Chapter 37, The Start-Up Files: init sysv [493]. 5.3.2. Configuring X From The Console To reconfigure X using XFdrake from the console, simply type XFdrake as root. Using XFdrake is no different to the graphical environment except that you won’t have nice icons and may not be able to use the mouse pointer. To move down you have to press the right or down arrow keys on your keyboard; to move up press the left or up keys on your keyboard. You can also use the Tab key to move between the different options/buttons. The text on the currently selected button/op tion will be highlighted with a different color. Press the Enter key to activate it. Please refer to Section 2, Controlling the Graphical Configuration [225] for instructions on its usage. 6. Bootloader Issues 6.1. Bootloader Reinstall It may happen that you make a mistake and wipe your disk’s MBR (Master Boot Record), or some misbehaving program erases it, or you dual boot with Windowsand catch a virus which suppresses it. So, you think you won’t be able to boot your system anymore, right? Wrong! There are many ways to recover the boot record. To recover your bootloader you need a boot disk. Without a boot disk of some kind you might be completely lost, unless you made a backup of your MBR, see Section 6.2, Backing Up and Restoring the MBR [366]. Reboot your computer using the boot disk. What you do next varies according whether you use LILO or GRUB. No matter which bootloader you use, all the commands you must execute need to be run as root. 6.1.1. With LILO If you use LILO, you only need to issue the following at the command prompt: /sbin/lilo. This command reinstalls LILO on your disk’s boot sector and fixes the problem.