May 24, 2017
Comments Off on Recovered from Catastrophic XenServer failure that made me Love Linux Even More
I now know why I really love Linux right now after totally losing my XenServer configuration due to some overheating in my home data center today. I reinstalled my XenServer server reattached storage to my XenServer server and then reattached the luns I had created with unique names to my VM with the former boot drive in position 0 in the VM, and then my home VG drive in position 1 then my game drive as position 2 and the server booted Centos 7 just fine! I had to reset the network interfaces on XenServer and VM plus sit through a Selinux re-label on boot and then voila I’m up and running again
This past week I have actually been dealing with overheating since it started dramatically warming up here in the Sacramento valley. I have been able to log in remotely and get my XenServer back up until today when even the IPMI connection went dead on me I knew the server was in trouble then!
When I got home I still thought I would be able to clear some logs in the bios and crash dumps in XenServer and things would be back up in about 30 minutes. Not today, I had been neglecting these babies too long!
I could not even boot off the safe mode kernel! For XenServer I could only get to the CLI in single-user and could not get past that. The system was complaining about not being able to mount a filesystem “/var/xen/xc-install”. The complete error was: “Failed to mount /var/xen/xc-install”.
I looked in /etc/fstab and sure enough it had the line:
- /opt/xensource/packages/iso/XenCenter.iso /var/xen/xc-install iso9660 loop ,ro 0 0
Well I could see the file /opt/xensource/packages/iso/XenCenter.iso and the mount point “/var/xen/xc-install “but when I did “mount –a” it said “filesystem type iso9660 unknown! I knew I had some module or kernel issues then or something else was royally corrupted. I played around with the basic XenServer commands then realized the cause was lost and I didn’t want to go forward with some kluge of a system.
I did try and upgrade with a XenServer 7.0 DVD but that produced an error message I didn’t bother to even notate something about a split. So I weighed my options and went for the clean install to my XenServer disk. I verified all my hardware was solid and in good shape even blew off some dust and reseated memory and storage controller cards in the XenServer.
Then booted up my FreeNAS primary server reattached the NFS share from there that has all my ISO’s for installing OS’ and was thinking I would boot off of the Centos 7 ISO and then “dd” all my boot drive then my home drive then may game drives to the new luns.
As I reattached my prior drives to the new VM I decided that if I the Linux Rescue CD could detect my old environment and I received a proper path like /dev/xvdN then I would try to position my drives old luns properly and boot my VM up Well that’s what I did and it worked as I explained above!
Maybe my Windows VM’s will come up just fine with this method as well. This however means that I will now bring both of my XenServers up to run once again in an HA ( Highly Available) configuration with my FreeNAS as storage instead of using local storage I had been using so I could cut down on my energy costs. The use of local storage seems dead now and it looks like I may have to bite the bullet on Solar since I haven’t found a place I want to move to yet! Ahh well the complications of life at least now I will not have to login and bounce my systems with IPMI or “wake on LAN”.
Well I have a lot of work ahead of me with these issues later this week and beyond so excuse the typos and grammatical errors for now I’m going to bed, I still get up pretty early!