Differences

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--- hypervisor:base:xcp-xapi [2015/03/29 00:36]
admin [Create and plug a VBD for the VDI]
+++ hypervisor:base:xcp-xapi [2015/03/29 04:46]
admin [kpartx for Mapping Partition Tables]
@@ Line 162: / Line 162: @@
 REPLACE: “openvswitch” with “bridge” (or vice-versa).
-===== Reboot =====
+==== Reboot ====
 After making those changes a reboot will be needed
@@ Line 174: / Line 174: @@
 It is often interesting to setup at least one VM to autostart at boot time.
-Do do so you can follow this next procedure:
+Do do so you can follow this next procedure, that is also described [[http://sysadmin.compxtreme.ro/autostart-vm-in-free-version-of-xenserver-6-x/|on this post]]:
 === Gather the UUIDs of the pools you wish to auto-start ===
@@ Line 206: / Line 206: @@
 > xe vm-param-set uuid=b7e42681-56c1-24cc-db45-9577981000b1 other-config:auto_poweron=true
+</code>
+=== Modify rc.local ===
+The previous steps are documented to be enough when using Citrix's XenServer. As we're using XCP/XAPI, one supplementary step is required, having a script to start at boot time all vms with "auto_poweron" in their other-config. This can be achieved by editing the //**/etc/rc.local**// file, adding the following code:
+<code>
+> nano /etc/rc.local
+#!/bin/sh -e
+#
+# rc.local
+#
+# This script is executed at the end of each multiuser runlevel.
+# Make sure that the script will "exit 0" on success or any other
+# value on error.
+#
+# In order to enable or disable this script just change the execution
+# bits.
+#
+# By default this script does nothing.
+[ -e /proc/xen ] || exit 0
+XAPI_START_TIMEOUT_SECONDS=240
+# wait for xapi to complete initialisation for a max of XAPI_START_TIMEOUT_SECONDS
+/usr/lib/xcp/bin/xapi-wait-init-complete ${XAPI_START_TIMEOUT_SECONDS}
+if [ $? -eq 0 ]; then
+pool=$(xe pool-list params=uuid --minimal 2> /dev/null)
+auto_poweron=$(xe pool-param-get uuid=${pool} param-name=other-config param-key=auto_poweron 2> /dev/null)
+if [ $? -eq 0 ] && [ "${auto_poweron}" = "true" ]; then
+logger "$0 auto_poweron is enabled on the pool-- this is an unsupported configuration."
+# if xapi init completed then start vms (best effort, don't report errors)
+xe vm-start other-config:auto_poweron=true power-state=halted --multiple >/dev/null 2>/dev/null || true
+fi
+fi
+</code>
+You can test that the code works using the following command, it is important to validate its function as line 19 may need to be adapted, i.e: YMMV for /usr/lib/xcp/bin/xapi-wait-init-complete
+<code>
+> /etc/rc.local
 </code>
 ----
-===== Create and Access a VDI from Dom0 =====
+===== Create and Access File Based VDI from Dom0 =====
+----
+The following procedure is based on the one described [[http://discussions.citrix.com/topic/334905-mount-vm-disk-image-as-file-system-in-xenserver-6/|in this post]].
 ----
 ==== Create the Virtual Hard Disk (VDI) ====
@@ Line 231: / Line 281: @@
 </code>
+We'll now have a new vhd file at:\\
+//**/run/sr-mount/<sr-uuid>/<vdi-uuid>.vhd**//
+Which, in our example, translates to:\\
+/run/sr-mount/26b9d87b-f344-1c8d-c5c5-a155d4e4e2e0/72e00fc6-98bb-48fe-ab4d-b52d1ef721b5.vhd
 ----
 ==== Create a VBD for the VDI and plug it ====
 ----
-=== Create VBD ===
+=== Create VBD (virtual block device) ===
 The newly created VBD will link our Dom0 to the VDI we just created, first let's recover our Dom0 UUID:
 <code>
@@ Line 244: / Line 299: @@
 </code>
-Then let's create and link the VBD (virtual block device) to our Dom:
+Then let's create and link the VBD to our Dom:
 <code>
 > xe vbd-create vm-uuid=76868e4b-4d82-320e-dd46-41340e6a67f3 vdi-uuid=72e00fc6-98bb-48fe-ab4d-b52d1ef721b5 device=autodetect
@@ Line 255: / Line 310: @@
 <code>
 > xe vbd-plug uuid=7472f458-ba3f-7344-99a7-6660a39037a6
+</code>
+At this stage, a new device will get listed under //**/dev/sm/backend/<sr-uuid>/<vdi-uuid>**// like:
+Before vdb-plug instruction:
+<code>
+ls -l /dev/sm/backend/26b9d87b-f344-1c8d-c5c5-a155d4e4e2e0/
+total 0
+brw------- 1 root root 253, 0 Mar 29 01:38 4ea98b0d-b3fc-4f62-86bd-19a80f7d356b
+</code>
+After vdb-plug instruction:
+<code>
+ls -l /dev/sm/backend/26b9d87b-f344-1c8d-c5c5-a155d4e4e2e0/
+total 0
+brw------- 1 root root 253, 0 Mar 29 01:38 4ea98b0d-b3fc-4f62-86bd-19a80f7d356b
+brw------- 1 root root 253, 1 Mar 29 01:59 72e00fc6-98bb-48fe-ab4d-b52d1ef721b5
 </code>
 ----
+==== kpartx for Mapping Partition Tables ====
+----
+The kpartx command creates device maps from partition tables. Each guest storage image has a partition table embedded in the file.
+We'll first need to install the package if it is not already available.
+<code>
+> apt-get install kpartx
+</code>
+=== Inspect an .img file ===
+kpartx lets you inspect an img file, showing its contained partitions using the -l command:
+<code>
+> kpartx -l /opt/xen/X-Local-ISO/<image_file_name>.img
+loop0p1 : 0 122880 /dev/loop0 8192
+loop0p3 : 0 1536000 /dev/loop0 131072
+loop deleted : /dev/loop0
+</code>
+----
+=== Add the partition mappings to the recognized devices in /dev/mapper/ ===
+<code>
+> kpartx -av /run/sr-mount/26b9d87b-f344-1c8d-c5c5-a155d4e4e2e0/72e00fc6-98bb-48fe-ab4d-b52d1ef721b5.vhd
+</code>
+==== END ====
+----
 ++++ X11 & VNC viewer |