Difference between revisions of "GSP Virtualisation with Xen"

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See
 
See
 
* http://docs.vmd.citrix.com/XenServer/5.5.0/1.0/en_gb/installation.html
 
* http://docs.vmd.citrix.com/XenServer/5.5.0/1.0/en_gb/installation.html
 
==== How NOT to do it ====
 
 
The default image format in an SR is based on "VHD" disk images, that are distributable across VMs and contain some (compressable) meta-data about sparseness. Overwriting an LVM which was ''supposed to contain'' an VHD image with a raw disk image will make the SR corrupt. So '''if''' you do:
 
* create a virtual disk with the default (XenCenter) tools in a SR
 
* then active the LV on an XCP server, e.g. with <tt>lvchange -a y /dev/VG_XenStorage-e5d0e83a-7e70-3d28-31ab-ed98bfb68368/VHD-74e94bbc-b0e5-4e76-b507-12897b9b2625</tt>
 
* copy the data from remove into this activates LV, and wait for it to complete (you '''cannot''' use the LV in a distributed setup as long as it is active on a single XCP host): <tt>dd if=/vm/mach/images/rooier.img bs=64M | ssh -A davidg@salado "ssh -A root@vms-piet-16.inst.ipmi.nikhef.nl 'dd of=/dev/VG_XenStorage-e5d0e83a-7e70-3d28-31ab-ed98bfb68368/VHD-74e94bbc-b0e5-4e76-b507-12897b9b2625 bs=64M'"</tt>
 
* de-activate the LV on the import host <tt>lvchange -a n /dev/VG_XenStorage-e5d0e83a-7e70-3d28-31ab-ed98bfb68368/VHD-74e94bbc-b0e5-4e76-b507-12897b9b2625</tt>
 
* create a new VM (typo "Other" seems to be needed) and use the newly-populated disk image as the disk for the VM
 
* try it out ...
 
'''it will break the SR''' and you loose all images on it (since the MGT data is support.
 
Recover using http://support.citrix.com/article/CTX122001:
 
# open a console on the master XCP server
 
# Back up LVM metadata
 
vgcfgbackup
 
# Run the following command to see the LV which is causing trouble and that is causing the SR not to be scanned.
 
lvscan
 
# Remove the clone logical volume. Note: Make sure the correct Logical Volume is deleted.
 
lvremove /dev/VG_ XenStorage-8d418f1a-107e-472f-5453-b24c88e7428e/VDI_8e4b4263-f9af-45f3-b97e-afa5481ea2a1
 
#.Run the following command to scan the SR, or use XenCenter
 
xe sr-scan uuid=<UUID of SR for the VM>.
 
 
You may need to forget about the SR first and then re-attach it (but DO NOT FORMAT the SR on attaching ;-)
 
  
 
== Connecting with FC ==
 
== Connecting with FC ==

Revision as of 17:51, 8 March 2012