Taking over management of a Xen box

So once in a while you get to take over the management of a machine someone installed with no documentation, with lots of playing around and no clue on how it should be reproducible. You're pretty sure that if you reboot the machine it won't come up with the right services, or in this case with the right Virtual machines up and running.

So I got this box with about 7 different xen configs in /etc/xen and none in /etc/xen/auto .. however different lvm volumes were created and 3 virtual machines were running. The different xen configs looked all the same.
web1, web, web.orig, web.working you know :(

So my challenge was to figure out the config of the running virtual machines
Luckily I bumped into some Redhat articles that tought me virsh dumpxml
Now I`m not really a fan of xml based config but it got me quite far.

Eg. on one of my own machines the output looks pretty good.

<br /> [root@core named]# xm list<br /> Name ID Mem(MiB) VCPUs State Time(s)<br /> Domain-0 0 619 1 r----- 1242.5<br /> web.hs62.be 1 511 1 -b---- 4648.2<br /> [root@core named]# virsh dumpxml 1


web.hs62.be
f7cb62b9d3aa8a07489604285fe3d842

linux
/boot/vmlinuz-2.6-xen
/boot/initrd-2.6-xen.img
/dev/sda1 rw
selinux=0 3

524288
1
destroy
restart
restart



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