Coloma is my old i386-PAE box. dual xeons in a supermicro chassis. kinda, well, old.
There were three problems. First, I let the userland xen tools get out of sync with the kernel. (uncontrolled yum update is not a good thing) Second, on this old box I never tested the 'save domains on reboot' functionality (on the new servers, if I reboot the dom0, it does an 'xm save' on every running DomU, and an 'xm restore' upon reboot, meaning that rather than seeing a reboot, the DomU owner might notice that the DomU was unavailable for 5-10 minutes, but everything that was running on it before was still running- it would be like unplugging the ethernet cable for a while and plugging it back in) The third (and perhaps largest) problem was that I rebooted the server to deal with the first problem without scheduling it (would have *maybe* been acceptable (but not good) on the new servers, but on the old ones, this was a mistake.)
I'll schedule things better in the future.
There were three problems. First, I let the userland xen tools get out of sync with the kernel. (uncontrolled yum update is not a good thing) Second, on this old box I never tested the 'save domains on reboot' functionality (on the new servers, if I reboot the dom0, it does an 'xm save' on every running DomU, and an 'xm restore' upon reboot, meaning that rather than seeing a reboot, the DomU owner might notice that the DomU was unavailable for 5-10 minutes, but everything that was running on it before was still running- it would be like unplugging the ethernet cable for a while and plugging it back in) The third (and perhaps largest) problem was that I rebooted the server to deal with the first problem without scheduling it (would have *maybe* been acceptable (but not good) on the new servers, but on the old ones, this was a mistake.)
I'll schedule things better in the future.
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