It took to me quite a while before I found a good, well documented, idiot-proof guide to this… that’s why I decided to save it in my own library.
All credits go to Dave Vehrs, and original article with all comments can be found here.
Also, one person nicknamed bombocat made a script to automate the whole process: Script to make the thing automagically…
This howto will explain how to install the base Debian GNU/Linux system onto a USB flash thumb drive.
So open your favorite root login shell and follow these 12 simple steps!
I. Load required kernel modules (if necessary)
Load any/all needed kernel modules (this is a partial list, actual list depends on your configuration):
root@hostname# modprobe ehci_hcd root@hostname# modprobe ohci_hcd root@hostname# modprobe usbhid root@hostname# modprobe usb_storage
II. Install required applications
Install the necessary applications on the build system:
root@hostname# apt-get install parted debootstrap
III. Identifying your media
The first thing we need to do is identify what our system identifies our media as. To do this, simply stick the usb thumbdrive into one of the usb ports and then run the tail command:
root@hostname# tail -n 14 /var/log/messages
Jan 1 12:00:00 hostname kernel: ohci_hcd 0000:00:02.1: wakeup
Jan 1 12:00:00 hostname kernel: usb 2-3: new full speed USB device using ohci_hcd
and address 2
Jan 1 12:00:00 hostname kernel: Initializing USB Mass Storage driver...
Jan 1 12:00:00 hostname kernel: scsi2 : SCSI emulation for USB Mass Storage devices
Jan 1 12:00:00 hostname kernel: usbcore: registered new driver usb-storage
Jan 1 12:00:00 hostname kernel: USB Mass Storage support registered.
Jan 1 12:00:00 hostname kernel: Vendor: Model: TS256MJFLASHA Rev: 1.00
Jan 1 12:00:00 hostname kernel: Type: Direct-Access ANSI SCSI
revision: 02
Jan 1 12:00:00 hostname kernel: SCSI device sda: 506400 512-byte hdwr sectors (259 MB)
Jan 1 12:00:00 hostname kernel: sda: Write Protect is off
Jan 1 12:00:00 hostname kernel: SCSI device sda: 506400 512-byte hdwr sectors (259 MB)
Jan 1 12:00:00 hostname kernel: sda: Write Protect is off
Jan 1 12:00:00 hostname kernel: sda: sda1 sda2
Jan 1 12:00:00 hostname kernel: sd 2:0:0:0: Attached scsi removable disk sda
root@hostname#
As we can see from this output, the device was detected and assigned to /dev/sda.
IV. Wipe the disk
The first thing we want to do is remove any old data from the drive. To do this, we’ll use the shred tool which overwrites the media with progressive cycles of random and nonrandom data to make recovery of any old data near impossible. As a final step, shred will overwrite everything with zeros.
root@hostname# shred -n 1 -z -v /dev/sda shred: /dev/sda: pass 1/2 (random)... shred: /dev/sda: pass 1/2 (random)...1.1MiB/248MiB 0% shred: /dev/sda: pass 1/2 (random)...2.4MiB/248MiB 0% shred: /dev/sda: pass 1/2 (random)...3.7MiB/248MiB 1% <SNIP> shred: /dev/sda: pass 2/2 (000000)...246MiB/248MiB 99% shred: /dev/sda: pass 2/2 (000000)...248MiB/248MiB 100% root@hostname#
For this example, shred wil run in verbose mode, with one overwrite pass of random data (-n 1) and then overwrite with zeros (-z).
V. Partition, format and mount the media
Next we need to partition the media. For a flash media installation, we will have a single partition and no swap.
For simple formating operations like this, I prefer to use GNU Parted because its a simple command.
- For small media (<=512mb)
-
root@hostname# parted /dev/sda "mklabel msdos mkpartfs primary ext2 0.0 -0 set 1 boot on" Information: Don't forget to update /etc/fstab, if necessary. root@hostname#Now that we have our partition, we need to create a temporary mount point and mount our partition to it so we can perform our install.
root@hostname# mkdir /mnt/buildroot root@hostname# mount -t ext2 /dev/sda1 /mnt/buildroot root@hostname#
- For large media (>512mb)
- Some BIOS will have difficulting seeing larger partition sizes on flash media, but the kernel does not have this limitation. So we can get around the problem by using a small /boot partition.
root@hostname# parted /dev/sda "mklabel msdos mkpartfs primary ext2 0.0 21.0 mkpartfs primary ext2 21.0 -0 set 1 boot on"Then mount like so:
mkdir /mnt/buildroot mount /dev/sda2 /mnt/buildroot mkdir /mnt/buildroot/boot mount /dev/sda1 /mnt/buildroot/boot
VI. Install base packages
Now that we have our partition mounted, we can install the base Debian system onto it.
root@hostname# debootstrap --arch i386 sid /mnt/buildroot I: Retrieving Release I: Retrieving Packages I: Validating Packages I: Resolving dependencies of required packages... I: Resolving dependencies of base packages... I: Found additional base dependencies: libdb4.2 libgnutls12 libreadline5 libsigc++-2.0-0c2a openbsd-inetd readline-common I: Checking component main on http://ftp.debian.org/debian... I: Retrieving adduser <SNIP> I: Configuring gnupg... I: Configuring sysklogd... I: Configuring klogd... I: Configuring netbase... I: Configuring openbsd-inetd... I: Base system installed successfully. root@hostname#
VII. Chroot Jail
root@hostname# chroot /mnt/buildroot /bin/su - hostname:~#
VIII. System Configuration
FILE: /etc/fstab
Use vi to create the /etc/fstab file and add these contents to it:
- For small media (<=512mb)
-
#/etc/fstab: static file system information. # /dev/sda1 / ext2 defaults,errors=remount-ro,noatime 0 1 proc /proc proc defaults 0 0 tmpfs /etc/network/run tmpfs defaults,noatime 0 0 tmpfs /tmp tmpfs defaults,noatime 0 0 tmpfs /var/lock tmpfs defaults,noatime 0 0 tmpfs /var/log tmpfs defaults,noatime 0 0 tmpfs /var/run tmpfs defaults,noatime 0 0 tmpfs /var/tmp tmpfs defaults,noatime 0 0
- For large media (>512mb)
-
#/etc/fstab: static file system information. # /dev/sda2 / ext2 defaults,errors=remount-ro,noatime 0 1 /dev/sda1 /boot ext2 defaults,noatime 0 1 proc /proc proc defaults 0 0 tmpfs /etc/network/run tmpfs defaults,noatime 0 0 tmpfs /tmp tmpfs defaults,noatime 0 0 tmpfs /var/lock tmpfs defaults,noatime 0 0 tmpfs /var/log tmpfs defaults,noatime 0 0 tmpfs /var/run tmpfs defaults,noatime 0 0 tmpfs /var/tmp tmpfs defaults,noatime 0 0
Then mount all the filesystems:
hostname:~# mount -a hostname:~#
Note: There maybe errors here that /dev/sda1 and /dev/sda2 can’t be found. It is safe to ignore them and continue.
Set Hostname
Set the hostname by editing /etc/hostname, and then add the base configuration to /etc/hosts:
127.0.0.1 localhost.localdoman localhost <hostname>
FILE: /etc/apt/sources.list
Next we have to add some sources to the Apt configuration.
deb http://ftp.debian.org/debian sid main non-free contrib deb-src http://ftp.debian.org/debian sid main non-free contrib deb http://mirrors.kernel.org/debian/ sid main non-free contrib deb-src http://mirrors.kernel.org/debian/ sid main non-free contrib
IX. Install additional packages and kernel
Start by updating the apt databases.
root@hostname# apt-get update Get:1 http://mirrors.kernel.org sid Release.gpg [189B] Get:2 http://mirrors.kernel.org sid Release [38.3kB] Get:3 http://mirrors.kernel.org sid/main Packages [4079kB] Get:4 http://ftp.debian.org sid Release.gpg [189B] Hit http://ftp.debian.org sid Release Hit http://ftp.debian.org sid/main Packages Get:5 http://ftp.debian.org sid/non-free Packages [74.6kB] Get:6 http://ftp.debian.org sid/contrib Packages [57.1kB] Get:7 http://ftp.debian.org sid/main Sources [1559kB] Get:8 http://ftp.debian.org sid/non-free Sources [30.3kB] Get:9 http://ftp.debian.org sid/contrib Sources [24.3kB] Get:10 http://mirrors.kernel.org sid/non-free Packages [74.6kB] Get:11 http://mirrors.kernel.org sid/contrib Packages [57.1kB] Get:12 http://mirrors.kernel.org sid/main Sources [1559kB] Get:13 http://mirrors.kernel.org sid/non-free Sources [30.3kB] Get:14 http://mirrors.kernel.org sid/contrib Sources [24.3kB] Fetched 7608kB in 48s (158kB/s) Reading package lists... Done root@hostname#
Install Localepurge
The first thing we’re going to install is localepurge to help keep the installation size down by removing all documentation in languages other than those you speak. When you install localepurge, it will ask you what locales you would like to keep. As an american english speaker, I select the following locales: en, en_us, and en_us.UTF8. Be careful not to remove too many locales or you may lose some functionality.
root@hostname$ apt-get install localepurge Reading package lists... Done Building dependency tree... Done Suggested packages: debfoster deborphan The following NEW packages will be installed localepurge 0 upgraded, 1 newly installed, 0 to remove and 30 not upgraded. Need to get 35.2kB of archives. After unpacking 87.0kB of additional disk space will be used. Get: 1 http://ftp.debian.org sid/main localepurge 0.4.1 [35.2kB] Fetched 35.2kB in 9s (3780B/s) Preconfiguring packages ... Configuring localepurge ----------------------- localepurge will remove all locale files from your system but the ones for the language codes you select now. Usually two character locales like "de" or "pt" rather than "de_DE" or "pt_BR" contain the major portion of localizations. So please select both for best support of your national language settings. The entries from /etc/locale.gen will be preselected if no prior configuration has been successfully completed. 1. aa 92. en_SG 183. ja_JP.UTF-8 274. se 2. aa_DJ 93. en_US 184. ka 275. se_NO 3. aa_ER 94. en_US.UTF-8 185. ka_GE 276. si 4. aa_ER@saaho 95. en_ZA 186. kk 277. si_LK 5. aa_ET 96. en_ZW 187. kk_KZ 278. sk <SNIP> 77. en 168. hy_AM 259. pt_BR 350. zh_CN 78. en_AU 169. ia 260. pt_PT 351. zh_CN.GB18030 79. en@boldquot 170. id 261. pt_PT@euro 352. zh_CN.GB2312 80. en_BW 171. id_ID 262. rm 353. zh_CN.GBK 81. en_CA 172. is 263. ro 354. zh_CN.UTF-8 82. en_DK 173. is_IS 264. ro_RO 355. zh_HK 83. en_GB 174. it 265. ru 356. zh_HK.UTF-8 84. en_GB.UTF-8 175. it_CH 266. ru_RU 357. zh_SG 85. en_HK 176. it_IT 267. ru_RU.KOI8-R 358. zh_TW 86. en_IE 177. it_IT@euro 268. ru_RU.UTF-8 359. zh_TW.Big5 87. en_IE@euro 178. iw 269. ru_UA 360. zh_TW.EUC-TW 88. en_IN 179. iw_IL 270. rw 361. zh_TW.UTF-8 89. en_NZ 180. ja 271. rw_RW 362. zu 90. en_PH 181. ja_JP 272. sa 363. zu_ZA 91. en@quot 182. ja_JP.EUC-JP 273. sa_IN (Enter the items you want to select, separated by spaces.) Selecting locale files 77 93 94 localepurge failed to preconfigure, with exit status 10 Selecting previously deselected package localepurge. (Reading database ... 79926 files and directories currently installed.) Unpacking localepurge (from .../localepurge_0.4.1_all.deb) ... Setting up localepurge (0.4.1) ... Configuring localepurge ----------------------- Based on the same locale information you chose above, localepurge can also delete superfluous localized man pages. Also delete localized man pages? yes If you are content with the selection of locales you chose to keep and don't want to care about whether to delete or keep newly found locales, just deselect this option to automatically remove new locales you probably wouldn't care about anyway. If you select this option, you will be given the opportunity to decide whether to keep or delete newly introduced locales. Inform about new locales? yes root@hostname#
After this, everytime you run apt-get to install or upgrade, it will post-install run localepurge to remove all unwanted documentation.
For now, we have to force it to run for the first time.
hostname:~# localepurge localepurge: Disk space freed in /usr/share/locale: 25396K hostname:~#
As space is limited, get in the habit of removing apt’s cached files frequently.
root@hostname# apt-get clean
Install Kernel
Before we can install the kernel, we need to set its configuration. Edit /etc/kernel-img.conf so that it looks like this:
do_symlinks = yes relative_links = yes do_bootloader = no do_bootfloppy = no do_initrd = yes ## <--- Verify this line link_in_boot = yes postinst_hook = /sbin/update-grub postrm_hook = /sbin/update-grub
Next we install the kernel.
hostname:~# apt-get install linux-image-2.6.16-1-686 Reading package lists... Done Building dependency tree... Done Suggested packages: linux-doc-2.6.16 linux-source-2.6.16 grub lilo Recommended packages: libc6-i686 The following NEW packages will be installed: linux-image-2.6.16-1-686 0 upgraded, 1 newly installed, 0 to remove and 2 not upgraded. 5 not fully installed or removed. Need to get 0B/15.7MB of archives. After unpacking 46.8MB of additional disk space will be used. Preconfiguring packages ... (Reading database ... 7204 files and directories currently installed.) Unpacking linux-image-2.6.16-1-686 (from .../linux-image-2.6.16-1-686_2.6.16-5_i386.deb) ... Done. Setting up busybox (1.01-4) ... Setting up libklibc (1.3.1-1) ... Setting up klibc-utils (1.3.1-1) ... Setting up udev (0.088-2) ... A chroot environment has been detected, udev not started. Setting up initramfs-tools (0.59b) ... wc: /proc/swaps: No such file or directory tail: cannot open `/proc/swaps' for reading: No such file or directory Setting up linux-image-2.6.16-1-686 (2.6.16-5) ... Hmm. The package shipped with a symbolic link /lib/modules/2.6.16-1-686/source However, I can not read it: No such file or directory Therefore, I am deleting /lib/modules/2.6.16-1-686/source Running depmod. Finding valid ramdisk creators. Using mkinitramfs-kpkg to build the ramdisk. Error, do this: mount -t proc none /proc hostname:~# apt-get clean hostname:~#
Install Bootloader (Grub or Lilo)
Either:
install the grub binaries:
root@hostname# apt-get install grub
Or:
install the lilo binaries:
root@hostname# apt-get install lilo
X. Exit the Chroot Jail
At this time, we need to exit the chroot
hostname:~# exit logout root@hostname #
XI. Install bootloader
Either: GRUB
To install grub into the bootsector
root@hostname# grub-install --recheck --root-directory=/mnt/buildroot /dev/sda Probing devices to guess BIOS drives. This may take a long time. Installation finished. No error reported. This is the contents of the device map /mnt/buildroot//boot/grub/device.map. Check if this is correct or not. If any of the lines is incorrect, fix it and re-run the script `grub-install'. (fd0) /dev/fd0 (hd0) /dev/hda (hd1) /dev/sda root@hostname#
Next we need to open /mnt/buildroot/boot/grub/menu.lst and add this configuration.:
- For small media (<=512mb)
-
# default num default 0 # timeout sec timeout 5 # pretty colours color green/black black/green title Debian GNU/Linux-2.6.16-1-686 root (hd0,0) kernel /vmlinuz-2.6.16-1-686 root=/dev/sda1 init=/sbin/init initrd /initrd.img-2.6.16-1-686 savedefault boot title Debian GNU/Linux-2.6.16-1-686 (Rescue/Single) root (hd0,0) kernel /vmlinuz-2.6.16-1-686 root=/dev/sda1 init=/sbin/init single initrd /initrd.img-2.6.16-1-686 boot
- For large media (>512mb)
-
# default num default 0 # timeout sec timeout 5 # pretty colours color green/black black/green title Debian GNU/Linux-2.6.16-1-686 root (hd0,0) kernel /vmlinuz-2.6.16-1-686 root=/dev/sda2 init=/sbin/init initrd /initrd.img-2.6.16-1-686 savedefault boot title Debian GNU/Linux-2.6.16-1-686 (Rescue/Single) root (hd0,0) kernel /vmlinuz-2.6.16-1-686 root=/dev/sda2 init=/sbin/init single initrd /initrd.img-2.6.16-1-686 boot
Then we need to run grub to link it all together
root@hostname# grub
Probing devices to guess BIOS drives. This may take a long time.
GNU GRUB version 0.97 (640K lower / 3072K upper memory)
[ Minimal BASH-like line editing is supported. For
the first word, TAB lists possible command
completions. Anywhere else TAB lists the possible
completions of a device/filename. ]
grub> root (hd1,0)
root (hd1,0)
Filesystem type is ext2fs, partition type 0x83
grub> setup (hd1)
setup (hd1)
Checking if "/boot/grub/stage1" exists... yes
Checking if "/boot/grub/stage2" exists... yes
Checking if "/boot/grub/e2fs_stage1_5" exists... yes
Running "embed /boot/grub/e2fs_stage1_5 (hd1)"...
failed (this is not fatal)
Running "embed /boot/grub/e2fs_stage1_5 (hd1,0)"...
failed (this is not fatal)
Running "install /boot/grub/stage1 (hd1) /boot/grub/stage2
p /boot/grub/menu.lst "... succeeded
Done.
grub> quit
Or: LILO
Edit /mnt/buildroot/etc/lilo.conf so that it looks similar to this:
- For small media (<=512mb)
-
boot=/dev/sda root=/dev/sda1 compact bitmap=/boot/sid.bmp bmp-colors=1,,0,2,,0 bmp-table=120p,173p,1,15,17 bmp-timer=254p,432p,1,0,0 install=bmp default=sid # install=menu map=/boot/map vga=normal delay=20 image=/boot/vmlinuz-2.6.16-1-686 label=sid root=/dev/sda1 read-only initrd=/boot/initrd.img-2.6.16-1-686
- For large media (>512mb)
-
boot=/dev/sda root=/dev/sda2 compact bitmap=/boot/sid.bmp bmp-colors=1,,0,2,,0 bmp-table=120p,173p,1,15,17 bmp-timer=254p,432p,1,0,0 install=bmp default=sid # install=menu map=/boot/map vga=normal delay=20 image=/boot/vmlinuz-2.6.16-1-686 label=sid root=/dev/sda2 read-only initrd=/boot/initrd.img-2.6.16-1-686
Then load the configuration into the master boot record
root@hostname# lilo -M /dev/sda # install MBR root@hostname# lilo -b /dev/sda # install lilo root@hostname#
Thanks to Rick Bronson for submitting the Lilo configuration on my original howto.
XII. Add user accounts
Either:
Copy an existing /etc/group, /etc/passwd, and /etc/shadow file over from another system (this has to be done from outside the chroot directory).
root@hostname# cp /etc/passwd /etc/group /etc/shadow /mnt/buildroot/etc/ root@hostname#
Then chroot in and create their homedirectories
root@hostname# chroot /mnt/buildroot /bin/su - hostname:~# mkdir /home/<username> hostname:~# chown <username>.<username> /home/<username> <Repeat as necessary> hostname:~# exit root@hostname#
Or:
Set root password and add users in the chroot
root@hostname# chroot /mnt/buildroot /bin/su -
hostname:~# passwd
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
hostname:~#adduser test
Adding user `test'...
Adding new group `test' (1001).
Adding new user `test' (1001) with group `test'.
Creating home directory `/home/test'.
Copying files from `/etc/skel'
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for test
Enter the new value, or press ENTER for the default
Full Name []: test
Room Number []:
Work Phone []:
Home Phone []:
Other []:
Is the information correct? [y/N] y
hostname:~#
<Repeat as necessary for more users>
hostname:~# exit
root@hostname#
And thats it. time to reboot and test.
