On Sat, Nov 07, 2015 at 07:57:05PM -0500, Jonathan Thornburg wrote: > At this point the machine can boot and run sd1[aeg] fine. *But* if I > enter "boot sr1d:/bsd" at the "boot>" prompt, the machine boots sd1[aeg], > not the desired sd1[dfh]. In other words, at this point my "backup" > sd1[dfh] partitions aren't usefully bootable :(.
You cannot boot a kernel from a non-'a' partition. The bootloader won't look elsewhere. In theory, you could copy your 5.6 kernel to the 'a' partition of your 5.8 install (cp /mnt/bsd /bsd.56) and then boot it from there with the '-a' option: boot> boot sr1a:/bsd.56 -a The '-a' option causes the kernel to ask for the root and swap partitions after booting, so you could try pointing this kernel at your 5.6 root filesystem on sd1d. But this is rather fragile. Perhaps it would have been easier to temporarily install 5.8 and your perl modules on a USB stick or into a qemu virtual machine for testing purposes. Overall, I'd suggest moving everything to 5.8 now and forgetting about your sinking 5.6 life boat. > I read with interest krw@'s recent Undeadly description > <http://www.undeadly.org/cgi?action=article&sid=20151101173739&mode=expanded&count=3> > of fixing a softraid-crypto bug in installboot(8), > | I spent some time helping stsp@ fix installboot(8) to handle softraid > | crypto installs, while stoutly maintaining my ignorance of softraid > | crypto. I failed to see a bug stsp@ introduced, which lead to some > | hilarity a few days later when I backed out the change at the same > | time that stsp@ was committing a real fix. Fortunately stsp@ was > | able to set things right, and installboot(8) now works for softraid > | crypto setups and non-softraid setups. > > Is this bug relevant to my situation? No. This bug didn't affect 5.8, it affected -current for about 2 days. Reading this quote it seems Ken got a bit confused in his report. The problem was not about softraid vs. non-softraid, but softraid on top of a GPT disk vs. softraid on top of an MBR disk. The bug broke boot entirely for softraid on an MBR disk (you would just see `ERR M' trying to boot).