Red hat Linux: Installation

I highly recommend that you choose "Custom Installation" mode and not Server or Workstation . Server and Workstation installation modes add pre-configured disk partitions which may wipe out stuff on drives you did not intend to disturb.A server-class installation does NOT install a GUI interface nor does it install X-windows. To install everything choose the "Custom" installation option. You can always turn off or ignore services and software you don't need.

[Potential Pitfall]: (RH 7.1) A server-class installation WILL erase all partitions both Linux and Non-Linux from every one of your computer's hard drives. This method will also put Lilo (or Grub) on the MBR. (Not good for Windows NT dual boot)

The "Automatic Partitioning" option (RH 7.1 and greater) is used by workstation, server and laptop class pre-configured installations and has the consequences of overwriting the MBR and re-partitioning all your drives. The "Manual" partition option is much more flexible.
Two manual partition tools are available:

1.      "Disk Druid" - I use this one

2.      fdisk

The auto option creates two partitions (/boot and /) and represents the most simple of installations. It is ideal for single user systems. A server or shared system may want to separate the users from the operating system by placing /home on a separate partition as well as /var and /opt. (More on this later)

Upgrades will be logged to the file /tmp/upgrade.log.

Linux installation is fairly intuitive except managing the disk partitions. The Linux CD-ROM is a boot disk, thus stick it in and re-boot your computer and the install menu will appear. If this does not work check your BIOS to see if your CD-ROM is in the list of boot devices. In my BIOS configuration I had to change the boot device default from A,C,SCSI to CDROM,C,A. After the installation was complete I changed it back. If you cannot boot from the CD-ROM, see instructions in section titled ``Creating a Linux boot floppy for Linux Installation'' in this guide. Most hardware is auto-detected during installation. The user is queried for the rest.

[Potential Pitfall]: (RH 7.2) RAID disk configuration requires text mode installation. Graphical GUI does NOT support RAID.

[Potential Pitfall]: (RH 6.1 and later) If the installation program presents itself as a text based console (DOS like) interface instead of a graphical based interface, chances are that the install program could not detect your graphics card and does not have the drivers for it.

Disk Druid: This is the disk partition manager. IDE drives are referred to as hda for the first drive, hdb for the second etc ... IDE uses separate ribbon cables for primary and secondary drives. The partitions on each drive are referred numerically. The first partition on the first drive is referred to as hda1, the second as hda2, the third as hda3 etc ... SCSI drives would be identified as sda, sdb ...

Linux IDE naming conventions:

Device	Description	Configuration
/dev/hda	1st (Primary) IDE controller	Master
/dev/hdb	1st (Primary) IDE controller	Slave
/dev/hdc	2nd (Secondary) IDE controller	Master
/dev/hdd	2nd (Secondary) IDE controller	Slave

If the CD-ROM was NOT recognized, restart from the Linux boot floppy and enter at the ``boot:'' prompt, linux hdX=cdrom, where X is a,b,c or d as described above.

Partitions: You will add at least three partitions. The first will be unnamed as a Linux swap partition of a given size i.e. 127Mb. (I'm generous and use at least twice the value of RAM memory on my system.) Add another as /boot of type ext2 Linux native and the third as /, Linux native ext3 (Red Hat native journaled file system) or LVM (logical volume manager: allows growing a file system by adding extra drives. Introduced in Red Hat Enterprise Linux 3 and Fedora Core) and [*] growable. The "growable" option takes whatever size is given as a minimum and actually allows the partition to take up the rest of the drive without actually specifying how much space is left. Use the space bar to toggle your choices between un-selected [ ] and selected [*]. (For RH 6.1 pick the select button.)

Mount Point	Size	Growable	Type
/boot	23Mb (RH9) 75Mb (RHEL4)	[ ]	Linux native (ext2) (no need to journal /boot)
_________	512 (for 256 Mb RAM) (Use RAM memory * 2)	[ ]	Linux swap
/	100	[*]	Linux native (ext3 or LVM)

The size of "/" set to 500 min. is arbitrary as the installer will use whatever is available because "Growable" is selected.

RHEL 4 defaults: boot-75Mb
RH 5.2/6.0 defaults: boot-16Mb, swap-127Mb

Descriptions:

• Swap - used for virtual memory (Use the larger value: 2 x physical memory or 127Mb. Red Hat 7.1 directions recommends at least 254Mb.
• /boot - Bootable operating system kernel is placed here. No need for a journaled file system thus you can use ext2. (ext3 will also work)
• / - All the rest of the UNIX files are placed under this directory
• /home - User directories. Server configurations often make this a separate partition so that user's disk resources are limited. Another way to limit user disk resources is to use the quota feature. See YoLinux.com quota tutorial
• /opt - Optional software added to the system. (Software which didn't come with the OS. Some user /usr/local.)
• /var - Files with variable or changing state and size (log files, print spool files, etc.) Server configurations often make this a separate partition so that bloated log files, spooled print jobs, etc are limited to the amount of space they can consume.
• /tmp - Temporary space used by the system and user services.
• /sbin - System admin commands
• /bin - Binaries (commands/executables) which everyone uses.
• /etc - Configuration files.
• /usr - User binaries (commands), documentation, ...
• /... - The rest: /dev - devices, /lib - libraries, /mnt - device mount point, /lost+found - repository of corrupt but repaired files, ...

See Compaq ProLiant Server recommendations.

Server installations: It is common practice to create more partitions to isolate user, system and temporary file directories. In this way, a user would not be able to fill up a drive and lock-up the computer, nor would the installation of large software packages or the generation of temporary files or log files. Create separate partitions for /home (user space), /opt (optional, non-standard software packages) or /usr/local, /tmp, /var etc... Making /home and /opt a separate partition from / also helps Linux upgrades which can be set to write over and upgrade all partitions except /home and /opt. Separating partitions and placing them on separate disk drives can also increase performance by reducing the load on a single drive.

My Workstation: If the installation is for your very own workstation which no one else is using, you can get away with three partitions, "/boot", "/" and swap. It gives ultimate disk flexibility (all disk space is available for whatever you want) but no protection from your own stupidity is enforced.

Other partitioning tools: fdisk is another disk partitioning tool.DOS, Linux and other version of fdisk exist. I recommend Red Hat s Disk Druid .

Note: The placement of /boot is limited by the Disk Druid tool to account for BIOS limitations. Although unlikely, you may not have these BIOS limitations, in which case, use fdisk to partition the drive and no limitations will be imposed.

Note: The /opt directory is often used to create a separate directory structure for commercial and "optional" software which is not part of the base install. This way it is a separate self-contained environment which is easy to backup and restore separately from the rest of the system. The directory structure will often mimic the / directory with /opt/bin, /opt/etc, /opt/lib etc...

Specialized device drivers: If your hardware is on the bleeding edge and does not have support built in with the Red Hat installation CD, then you must provide the device driver during installation. Typically the Red Hat installation software will recognize that it does not have a driver for the hardware detected. For example: Red Hat 8.0 and the Adaptec U320 SCSI driver:

• Download the host bus adapter floppy image.
• Unzip the file: gzip -d aicXX..-i686-rh8.0.img.gz
• Copy floppy image to floppy: dd if=aicXX..-i686-rh8.0.img of=/dev/fd0 bs=1440k

The Red Hat installation program will request the missing driver. Load the floppy when asked: "No drivers found - would you like to select drivers now?". Select "yes". Press "F2" to provide the SCSI driver on a floppy and continue with the installation.

Other Installation Methods: This tutorial covers installation from a CR-ROM. It should be pointed out that Linux may also be installed from an NFS server, by FTP, SMB (a windows shared drive) and from a local hard drive.

[Potential Pitfall]: If using IDE, note that most BIOS's requires /boot be installed on a drive attached to the Primary controller. If using two IDE hard drives it might be best to place them on the primary controller and place the CD-ROM on the Secondary .

[Potential Pitfall]: When using SCSI devices, the /boot partition must reside on SCSI ID 0 or 1.

[Potential Pitfall RH7.0 and earlier]: NOTE: The /boot partition must be completely placed within the first 1024 cylinders of the disk. This drive geometry information is presented by Disk Druid under the heading Geom. The symbols [C / H / S] represent [Cylinders / Heads / Sectors] of the drive. (This is one reason why it may be easiest to install Linux on a separate drive and place the /boot partition at the beginning of the drive.) RH 7.1 introduced a newer version of LILO with LBA32 support which corrects this limitation. Red Hat 7.2 has even fewer restrictions. In fact RH 7.2 introduces new features which allow flexibility in choosing location and placement of file systems, boot loaders and kernel on your drive.

[Potential Pitfall]: I had one installation where I selected the "Check for bad blocks" while formatting and it caused the install to lock up. On this particular system I had to skip this check.

[Potential Pitfall]: If the hard drive was 100% entirely formatted for windows, there will be no space for Linux partitions. During the install you must select the windows partition and delete it before adding new partitions and assigning percentages.

Lets Do The Install: Partitions and mount points which are already allocated, are listed at the top of the screen. Use the "Tab" key to get to "Add" if you want to create a new partition for Linux. Use the "Tab" key to get to "Delete" , if you are going to put Linux on a partition previously used for DOS and then "Add" it as a new Linux partition.
Tab to the hard drive selection box which will have all drives selected.

       [*] hda
       [*] hdb

Tab to the drive you don't want to use and press the space bar to un-select.

       [ ] hda
       [*] hdb

Now add the partitions for /boot, /root (optional), "/" and swap (and any others you wish to add) as described above.

Lilo Text Boot Options:

• boot: text - No GUI. Console text mode only.
• boot: linux text console=ttyS0 - For use with a serial terminal
• boot: linux isa - To explicitly request ISA configuration dialog
• boot: linux mediacheck - Check ISO CD integrity

Red Hat 7.2 upgrade/install: EXT3 The 7.2 upgrade allows one to upgrade the Linux EXT2 file system to EXT3. EXT3 is a journaled file system which is crash resistant, insuring the integrity of the data even if the system crashes during a system write because it journals the transaction before it undertakes a disk write. I recommend the EXT3 upgrade. The RH 7.2 EXT3 upgrade will also disable periodic file system checks as it assumes that file system integrity is maintained. (See autofsck) Use tune2fs (-c or -i) to re-enable check. EXT3 is the default file system for a fresh Red Hat 7.2 installation. EXT3 may be installed in one of three modes:

• ordered: Default. Crash will result in a valid non-corrupted file system.
• journal: slow
• writeback: Fast but NOT crashproof.

The option is also specified in the file /etc/fstab with the string 'data=ordered'.

Also note that Red Hat 7.2 does NOT include a "Powertools" CD. Most of the "Powertools" packages have been included as part of the base installation.