sysadmin-sop: add guest migration doc

Signed-off-by: Mark O Brien <markobri@redhat.com>

modules/sysadmin_guide/pages/guest_migrate.adoc

@@ -0,0 +1,73 @@
+= Guest migration between hosts.
+
+Move guests from one host to another.
+
+== Contact Information
+
+Owner::
+  Fedora Infrastructure Team
+Contact::
+  #fedora-admin, sysadmin-main
+Location::
+  IAD2, Tummy, ibiblio, Telia, OSUOSL
+Servers::
+  All xen servers, kvm/libvirt servers.
+Purpose::
+  Migrate guests
+
+== How to do it
+
+[arabic]
+. Schedule outage time if any. This will need to be long enough to copy
+the data from one host to another, so will depend on guest disk size.
+. Turn off monitoring in nagios
+. On new host create disk space for server:
++
+....
+lvcreate -n app03 -L 32G vg_guests
+....
+. prepare old guest for migration:
+[loweralpha]
+.. if system is xen, install a regular kernel
+.. look for entries for xenblk and hvc0 in /etc files
+. Shutdown the guest.
+. {blank}
++
+....
+virsh dumpxml guestname > guest.xml
+....
+. Copy guest.xml to the new machine. You will need to make various edits
+depending on if the system was originally xen or such. I normally need
+to compare an existing xml on the target system and the one we dumped
+out to make up the differences.
+. Define the guest on the new machine: 'virsh define guest.xml'.
+Depending on the changes in the xml this may not work and you will need
+to make many manual changes plus copy the guest.xml to
+`/etc/libvirtd/qemu` and do a `/sbin/service libvirtd restart`
+. Insert iptables rule for nc transfer:
++
+....
+iptables -I INPUT -s <source host> -m tcp -p tcp --dport 11111 -j ACCEPT
+....
+. On the destination host:
++
+____
+nc -l 11111 | dd of=/dev/mapper/<guest-partition>
+____
+. On the source host:
++
+....
+dd if=/dev/mapper/guest-partition | nc <desthost> 11111
+....
++
+Wait for the copy to finish. You can do the following to track how far
+something has gone by finding the dd pid and then sending a 'kill -USR1'
+to it.
+. start the guest on the new host:
++
+....
+``virsh start guest``
+....
+. On the source host, rename storage and undefine guest so it's not
+started.
+. In ansible change the host_vars to reflect the new host