OS Builder/Run on XO hardware

It is usually possible, if a bit slow, to run OS builder on XO hardware. On platforms where fast machines are available (such as x86), using a server-class "builder" machine is recommended.

When resources are limited, or if server-class machines are not available for the platform (such as ARM), this recipe is recommended.

The procedure has been tested with XO-1.5, XO-1.75 and XO-4 hardware and 13.2.0-13.

Ingredients

Each of these must be dedicated to the task for as long as you need to make builds:

• an XO-1.5, XO-1.75 or XO-4<ref>use an XO-1.5 to make XO-1 or XO-1.5 builds, and use an XO-1.75 or XO-4 to make XO-1.75 or XO-4 builds.</ref>,
• optional<ref>we have tested without swap on XO-1.5, XO-1.75 and XO-4, each of which have at least 1GB of RAM.</ref>; an SD card for swap; minimum size 512 MB, good quality, fast access, e.g. class 10,
• a USB hard disk drive for storing RPMs and build files; minimum size 120 GB, fast, large capacity,
• an unfiltered internet connection<ref>the builder must be able to download files from repositories, and filtering may prevent file downloads, in particular one user reported RPMs starting with the name tracker were blocked.</ref>.

Recipe

• install 13.2.0-13,
• boot to Sugar or Gnome, log in, and connect to your wireless network,
• optional; insert a USB ethernet adapter and connect to your wired network,
• disable automatic power management from the Sugar control panel, or in Gnome:

 sudo touch /etc/powerd/flags/inhibit-suspend

• configure the system to keep documentation after package installation<ref>this is needed so that the example files in olpc-os-builder are kept, which are classified as documentation for the olpc-os-builder package, and are deleted by default on OLPC OS</ref>:

 sudo sed -i '/excludedocs/d' /etc/rpm/macros.imgcreate

• install some packages:

 sudo yum install -y ntpdate gparted olpc-os-builder binutils git gcc make libtomcrypt-devel zlib-devel

• ensure the system date and time are correct:

 sudo ntpdate pool.ntp.org

• optional; insert external SD card, and prepare it for swap using gparted, Applications -> System Tools -> GParted Partition Editor, then add it to the filesystem table:

 eval $(blkid -o export /dev/mmcblk1p1)               # get the UUID
 echo UUID=$UUID swap swap defaults 0 0 >> /etc/fstab # add to table
 swapon -a -v                                         # enable swap

• prepare the USB hard drive using gparted, Applications -> System Tools -> GParted Partition Editor, partitioning it with a large ext4 partition, then add it to the filesystem table:

 eval $(blkid -o export /dev/sda1)                    # get the UUID
 umount $DEVNAME
 mkdir /oob
 echo UUID=$UUID /oob ext4 auto,rw 0 0 >> /etc/fstab  # add to table
 mount -a                                             # mount the filesystem

• download v7.0 of olpc-os-builder to the USB hard drive:

 cd /oob                                                         # change directory
 git clone -b v7.0 git://dev.laptop.org/projects/olpc-os-builder # download
 cd olpc-os-builder                                              # change directory

• customise your build to make it build faster, by editing examples/olpc-os-13.2.1-xo4.ini
  • remove the [usb_update] module,
  • in the [base] module, set versioned_fs=0 and make_tree_tarball=0,
  • reduce the [global] langs= to the languages you need,

Your setup is ready, you can now make the first build:

 sudo ./osbuilder.py examples/olpc-os-13.2.1-xo4.ini

The first build will take much longer than subsequent builds, because it will download RPMs and activities to disk.

Experiences

On XO-1.5, XO-1.75 and XO-4 with a typical USB hard drive, the build takes between half an hour and an hour on subsequent runs. See experiences for further detail.

Notes

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