EXPERIMENTAL Xen guest domain installation for SLC 3.0.8 / i386

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 SLC3.0.8 'CERN Recommended Setup' default installation type.

PLEASE NOTE: Since support for SLC3/x86_64 and SLC3/ia64 architectures ends December 2006 Xen guest systems will NOT be provided for these architectures.

Installation instructions

• edit /etc/xen/SLC308guest configuration file

     name = "SLC308guest"
     memory = 512
     #vcpus = 2
     disk = [ 'file:/somewhere_somefile.img,sda,w' ]
     vif = [ 'mac=00:16:3E:XX:XX:XX' ]
     #bootloader="/usr/bin/pygrub"
     on_reboot   = 'destroy'
     on_crash    = 'destroy'
     on_poweroff = 'destroy'

(create /somewhere_somefile.img with dd , at least 5GB needed..)

NOTE: for SLC 3.0.8 para-virtualized guest ONLY A SINGLE sda virtual disk is supported (after installation additional devices may be added to the system)

NOTE: MAC address should start with 00:16:3E - this is Xensource reserved range allowed for public Xen-related usage.

Starting the guest installation

• download installation kernel and ramdisk from:

  http://linuxsoft.cern.ch/cern/slc308/i386/images/xen/

• run:

      /usr/sbin/xm create SLC308guest -c \
                 kernel=vmlinuz \
                 ramdisk=initrd.img \
                 extra="method=http://linuxsoft.cern.ch/cern/slc308/i386/ ramdisk_size=16384 serial skipddc"

NOTE: serial IS needed , or installer will crash on hardware detection.

NOTE: skipddc IS needed, or kernel will crash on hardware detection.

The installation procedure looks exactly the same as standard SLC3 installation on real hardware.

Post installation setup

• after installation finished edit /etc/xen/SLC308guest again

     name = "SLC308guest"
     memory = 512
     #vcpus = 2
     disk = [ 'file:/somewhere_somefile.img,sda,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 SLC308guest (-c)

Automatic startup of guest domain

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

     /bin/ln -s /etc/xen/SLC308guest /etc/xen/auto/

Finalizing guest domain setup

After guest domain reboots it will have configured additional apt repository for Xen-enabled kernels/glibc .. etc. (SO PLEASE ignore the warning about /lib/tls on first boot , just check that after update you have glibc-X.Y.Z.xen installed)

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 ..)

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

Management of Xen domains

• Please see XenUserGuide for information.