On Sep 4, 2022, at 10:05, Doug Denault <doug@safeport.com> = wrote:

There was a long thread on this. My observations and = questions are more about how to update production systems. My long = standing update path is to update my FreeBSD workstations. If that goes = okay we some servers on out LAN that we update next.

I ran `freebsd-update -r 12.3-RELEASE upgrade` which = converted my laptop essentially into a paperweight by the introduction a = bad copy of ld-elf.so.1. The system would boot, but most useful commands = (think cp) exited with an error. This is all documented via google with = no successful work arounds that I could fine. What you can not do is = `freebsd-update rollback`. I though I could maybe fix this by going to = single user and overwriting ld-elf.so.1. This can not be done as all = commands depend on this file.

I created = image files from:

= FreeBSD-12.3-RELEASE-amd64-dvd1.iso (4+GB)
= FreeBSD-12.3-RELEASE-amd64-memstick.img ~1GB

Neither of these images are self contained. Both install 12.3 = correctly but by downloading the OS from a mirror site of your choosing. = Is there a path thought the dvd1 install that does something with the = extra 3GB of data? Does the dvd1.iso image have to be burned to a = DVD?

dvd1 includes a bunch of extra local packages, = it's otherwise identical to cd1.

You = should have a bunch of static binaries in /rescue which include = cp.

I've been bitten by this several = times in the past (on machines in faraway countries, where my only = access was a serial console), where all of a sudden midway through a = freebsd update install I'll just see a bunch of segfaults, and I'm still = not sure what's happening to cause it, but my solution has been to = *before I update* grab a spare tar file for base.txz for my target OS, = just in case.

My am not sure what is the = philosophy of deleting the supporting files so quickly. Other than = making a system from backup is there a way to install an older = version?

Yes. Grab the base.txz files from ftp.freebsd.org or = ftp-archive.freebsd.org, or from your boot cdrom. = Untar them over /, and you should have a working linker back. I = would not call that "a production system" but it should be stable enough = to let your system attempt to redo the upgrade.

Yes, freebsd-update is bad at recovering from this = failure mode. The rollback function really is only good for = rolling back patchlevels, not major upgrades. Nor does it have a = "wait, you're a shell script, please just use the static files in = /rescue, and re-attempt the install" function.

FreeBSD really should have "ftp" or "fetch" or = "scp" or something in /rescue, but there is at least nc, which you = can use to get a file on to the box, albeit slowly.

-Dan