Thanks for all your answers. I had the opportunity to see the console screen and it turned out that the file system was started in read-only mode. The dmesg was full of "read-only" messages.
After doing a few fscks in single user mode, the system started up fine. The real question is; this is a VPS, I always (occasionally) issued clean resets/shutdowns, and how did it get like this? And by the way, what does the -F switch in the "MARK FILESYSTEM CLEAN" question do? I would always do 'y'. Best, Mark. On Fri, Oct 11, 2024 at 7:22 AM Nick Holland <n...@holland-consulting.net> wrote: > > On 10/10/24 14:14, Sebastien Marie wrote: > > Mark <markbsdmail2...@gmail.com> writes: > > > >> Hi. > >> > >> I got 2 VPS, yesterday I upgraded one, from OpenBSD 7.5 to OpenBSD 7.6 > >> (amd64), > >> today I wanted to upgrade the remaining one, after "sysupgrade -nk" and > >> "reboot", > >> > >> I cannot login to the system anymore (I manage only via SSH), Putty says: > >> "Remote side unexpectedly closed network connection", > >> after entering the password of my root user. I tried ssh in the Windows > >> terminal, same thing happens. > >> > >> ssh server is running, login: prompt arrives. And I see that my ssh client > >> disconnects after issuing the correct password. > >> > >> If the password is wrong, it attempts to ask for it again. > >> > >> I got no physical or console access to the server. > >> > >> Any idea would be much appreciated. > > > >>From your description, I assume your shell is from ports (bash, zsh, > > ...), and that after the upgrade of base, the binary of the port (from > > 7.5) doesn't run on 7.6 system for some reason. So, sshd runs (it is > > 7.6), you connect : sshd execve the shell, and it doesn't ends well. > > that was my first assumption, too. > > > You can try to connect to another user (if possible) using some base > > shell, or try to get a console (the getty) and logs as root (assuming > > the shell of root is still ksh). > > Might try this: > ssh remotehost ksh > > it will probably look like it hung, but it might not be -- you are just > sitting at ksh without $PS1 (or much of anything else) set. You might > be able to gain control of the system sufficiently to run pkg_add -u. > > Here's an actual demo: > $ uname -a > OpenBSD fluffy3.in.nickh.org 7.5 GENERIC.MP#171 amd64 > $ ssh dbu1 ksh > uname -a # note lack of prompt, motd, or anything... > OpenBSD dbu1.in.nickh.org 7.6 GENERIC.MP#337 amd64 > # but I'm in! > > you can get around some of the no prompt/no motd stuff by > doing "ssh <host> ksh -li", but it's still quite weird. > > you know all those times when you said, "I don't need to know > 'ed(1)'"? well...maybe you now need it. > > Warning: when I promoted myself to root, the PW echoed on the screen. > So...beware of shoulder surfers. :) > (and I'm sure there are fixes for all these issues, but I didn't hunt > very hard) > > Nick. >
