OpenVZ for Tilera


== Prerequisites ==

You have to have Tilera MDE installed in the following way:

 gpg -d /path/to/tileramde-3.0.0.123096_tilepro.tar.bz2.gpg | tar xjf -
 gpg -d /path/to/tileramde-3.0.0.123096_tilepro_src.tar.bz2.gpg | tar xjf -
 eval $(TileraMDE-3.0.0.123096/tilepro/tile-env)
 cd $TILERA_ROOT
 gpg -d /path/to/tileramde-3.0.0.123096_tilepro_tile.tar.bz2.gpg | tar xjf -
 cat << EOF > tile/.profile
 HOME=/root
 cd
 EOF

In other words:
* tilepro and tilepro_src tarballs are unpacked to the same directory
* tilepro_tile tarball is unpacked under $TILERA_ROOT
* $TILERA_ROOT/tile/.profile is created as shown above

== Creating OpenVZ template ==

A template is just a tarball of a Linux distribution installed into
a chroot-like environment. Here, we can just use $TILERA_ROOT/tile contents,
omitting just some less-needed contents:

 cd $TILERA_ROOT/tile
 tar cvzf ../tile.tar.gz . \
  --exclude ./boot \
  --exclude ./lib/modules \
  --exclude ./usr/share/doc \
  --exclude ./usr/share/locale

== Compile/install vzctl ==

vzctl is a tool to control OpenVZ containers. To compile it:

 cd $TILERA_ROOT
 TAR=vzctl-tilera-20110429-3.tar.bz2
 wget http://download.openvz.org/.kir/tilera/$TAR
 tar xvjf $TAR
 rm -rf vbuild
 mkdir vbuild
 cd vbuild
 sh ../src/packages/vzctl/tile-extract
 ./tile-build --install

At this point you should have vzctl installed into $TILERA_ROOT/tile

In addition, put the OpenVZ template into an appropriate directory:

 cd $TILERA_ROOT
 cp tile.tar.gz tile/vz/template/cache/

== Compile/install OpenVZ kernel ==

This kernel is based on RHEL6-2.6.32 plus OpenVZ patches 042test008.1,
plus backported Tilera patches taken from Tilera MDE 3.0.0.123096
2.6.36 kernel source.

This is an initial port, with some known bugs and limitations.

FIXME: what options/features are not yet ported?

Here is how to compile OpenVZ kernel:

 cd $TILERA_ROOT
 TAR=kernel-rhel6-ovz-tilera-20110429.tar.bz2
 wget http://download.openvz.org/.kir/tilera/$TAR
 tar xjf $TAR
 mkdir kbuild
 cd kbuild
 export ARCH=tile
 sh $TILERA_ROOT/src/sys/rhel6-ovz-kernel/tile-prepare
 make -j32
 make modules_install INSTALL_MOD_PATH=$TILERA_ROOT/tile/

== Running OpenVZ ==

=== Preparing a chroot script ===

 cat << EOF > $TILERA_ROOT/tile/chroot.sh
 cd /mnt
 mount --bind /sys sys
 mount --bind /proc proc
 mount -t tmpfs tmpfs /mnt/dev
 cp -a /dev/ /mnt/
 chroot . /bin/bash
 # Rollback
 umount /mnt/dev
 umount /mnt/sys
 umount /mnt/proc
 EOF

=== Running kernel ===

 cd $TILERA_ROOT/kbuild
 tile-monitor --vmlinux vmlinux --pci --mount $TILERA_ROOT/tile/ /mnt/

=== Running OpenVZ ===

In another shell session, run screen in order to access console.

 screen -S console /dev/ttyS1 115200

In the screen session, switch to chroot using the script prepared before:

 /mnt/chroot.sh

You should now see bash prompt (bash-4.1#).

Next, start OpenVZ:

 /etc/init.d/vzeventd start
 /etc/init.d/vz start

Before creating a container, we should disable DISK_QUOTA in global
OpenVZ configuration file (vzquota utility is not yet ported to Tilera):

 sed -i s/^DISK_QUOTA=.*$/DISK_QUOTA=no/ /etc/vz/vz.conf

Now we can create our first container. The following command will take the
tarball /vz/template/cache/tile.tar.gz and unpack it into /vz/private/101.
It also creates /vz/root/101 and a container config file
/etc/vz/conf/101.conf.

 vzctl create 101 --ostemplate tile

NOTE: creation takes quite a long time because of sheperd-fuse mount being
used. I do not know of any better way to access a host system's FS from
inside the Tilera environment.

Next we can start the freshly created container:

 vzctl start 101