TEST Xen guest domain installation for SLC 4.X / i386 or SLC 4.X / x86_64

PLEASE NOTE: This is Work In Progress and NOT production quality release: it may or may not work for you ... remember: if it breaks you have to keep both pieces ... and YMMV ..

This installation procedure concerns ONLY para-virtualized Xen guest systems.

This installation procedure was tested ONLY with SLC 4.X 'CERN Recommended Setup' default installation type.

Installation instructions

• edit /etc/xen/SLC4Xguest configuration file

  name = "SLC4Xguest"
  memory = 512
  disk = [ 'file:/somewhere_somefile.img,xvda,w' ]
  vif = [ 'mac=00:16:3E:XX:XX:XX' ]
  on_reboot   = 'destroy'
  on_crash    = 'destroy'
  on_poweroff = 'destroy'

(create /somewhere_somefile.img with dd , at least 5GB needed.. see PreparingXenGuestFilesystems for a more detailed description howto prepare the guest filesysems)

NOTE: MAC address should start with 00:16:3E - this is Xensource reserved range allowed for public Xen-related usage. If on the CERN network, please register your MAC address in LanDB, otherwise you will not be able to use DHCP.

Starting the guest installation

• For SLC 4.X (>=5) / i386 guest, download installation kernel and ramdisk (vmlinuz and initrd.img) from:

  http://linuxsoft.cern.ch/cern/slc4X/i386/images/SL/xen/

• run:

      /usr/sbin/xm create SLC4Xguest -c \
                 kernel=vmlinuz \
                 ramdisk=initrd.img \
                 extra="method=http://linuxsoft.cern.ch/cern/slc4X/i386/"

• For SLC4.X / x86_64 guest, download installation kernel and ramdisk (vmlinuz and initrd.img) from:

  http://linuxsoft.cern.ch/cern/slc4X/x86_64/images/SL/xen/

• run:

      /usr/sbin/xm create SLC4Xguest -c \
                 kernel=vmlinuz \
                 ramdisk=initrd.img \
                 extra="method=http://linuxsoft.cern.ch/cern/slc4X/x86_64/"

The installation procedure looks exactly the same as standard SLC4 installation on real hardware. In particular, you can use Kickstart to script the installation if you start your virtual machine like

/usr/sbin/xm create SLC4Xguest -c \
               kernel=vmlinuz \
               ramdisk=initrd.img \
               extra="method=http://linuxsoft.cern.ch/cern/slc4X/{i386,x86_64}/  ks=http://linuxsoft.cern.ch/kickstart/dir/yourkickstartfile.ks serial"

(other useful parameters for the "extra" argument can be found at usr/share/doc/anaconda-X.Y.Z/command-line.txt, e.g. ip=A.B.C.D netmask=E.F.0.0 gateway=G.H.I.J dns=K.L.M.N,O.P.Q.R for machines without DHCP).

Known installation problems

The x86_64 SLC4.5 paravirtualized guest hangs on last installation stage: bootloader installation and stays there forever. In order to proceed use this workaround:

Press Ctrl-] to disconnect virtual console.

Use xm destroy SLC4Xguest

After editing /etc/xen/SLC4Xguest file

use xm create SLC4Xguest -c to restart the guest

Post installation setup

• after installation finished edit /etc/xen/SLC4Xguest again

  name = "SLC4Xguest"
  memory = 512
  disk = [ 'file:/somewhere_somefile.img,xvda,w' ]
  vif = [ 'mac=00:16:3E:XX:XX:XX' ]
  bootloader="/usr/bin/pygrub"
  on_reboot   = 'restart'
  on_crash    = 'restart'
  on_poweroff = 'destroy'

Running the guest domain

• To start the guest run

      /usr/sbin/xm create SLC4Xguest (-c)

Automatic startup of guest domain

• if you want the domain to be (re)started by Xen automatically:

     /bin/ln -s /etc/xen/SLC4Xguest /etc/xen/auto/

Finalizing guest domain setup

Since the graphical installer is not supported in virtualized guests for now, you will have to configure your system for CERN setup manually:

   /usr/sbin/lcm --configure --all
   /sbin/chkconfig --levels 345 afs on
   /sbin/service afs start
   /usr/sbin/lcm --update

Also disable the CPU microcode update (after all we are running on virtual CPUs ...) and SMART disk monitoring (we are running on virtual disks too ..) The hardware clock cannot be set either, so NTP is useless on the client (but you want it to run on the hypervisor).

   /sbin/service microcode_ctl stop
   /sbin/chkconfig --del microcode_ctl
   /sbin/service smartd stop
   /sbin/chkconfig --del smartd
   /sbin/service ntpd stop
   /sbin/chkconfig --del ntpd

---+++ Management of Xen domains
   * Please see XenUserGuide for information.

-- Main.JaroslawPolok - 22 May 2007