| From: Kevin Cozens <kevin@ve3syb.ca> | On 15-08-09 11:11 AM, D. Hugh Redelmeier wrote: | > I took an Acer Revo out of service as an HTPC. It was dual boot Win 7 and | > Ubuntu 12.04 LTS. | [snip] | > It offered me Ubuntu 14.04 LTS. | You jumped over 3 other releases in between. One of which would have been | another LTS release. Actually, the LTS update path is from 12.04 LTS to 14.04 LTS as one step. There was no LTS between these. Perhaps less visible is that the first time migration is suggested is when 14.04.1 LTS was released, not 14.04. So no, what I did was purely by the book. Ubuntu understands and promotes the LTS-only approach | > Negative observation two: I thought that the slow upgrade process could | > happen while I was asleep. | | I prefer to do the updates during the day so I can keep an eye on it. There | are extra questions that can be asked of you during an install that would | bring the process to a halt until an answer is provided. Quite. That should not be required. | > So I rebooted. Now I have the prompt: | > grub rescue> | This could be one of a few issues. It could be a failed update to the grub | bootloader, Yeah, not good. | it could be the Windows update changed the boot partitions or | removed the grub bootloader, No: LINUX booted after the last time Windows was booted. | or possibly a UEFI related boot issue. No: no UEFI on this old BIOS. | If (or, rather when) Windows update messed with the bootloader it usually | makes it so the system boots straight to Windows. Seeing a grub prompt means | that is not the case here. Window frequently invents new ways not getting along with Linux, often related to booting. Many of the newer and more mysterious ones involve UEFI. For one thing, all systems need to share /boot/efi. Thanks for the grub hints (not quoted). Grub is a complex, powerful, and idiosyncratic tool doing a confusing task. And since it usually works we have little incentive to learn of its commands. It turns out that the "grub rescue>" prompt isn't totally useless. Most of the Grub machinery isn't available, but there is enough that one might be able to climb out of the hole.