Re:An Ubuntu kernel bug causes container crashes
by withinboredom on Wednesday July 06, 2022 @04:44AM
(#31998353)
Sounds like a VM and not a physical server.
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Re:An Ubuntu kernel bug causes container crashes
by laumars on Wednesday July 06, 2022 @05:21AM
(#31998576)
Nope. Back before VMs were thing it was common to do "lights out" style remote management via a console server. That console server would then have a serial connection (the old 9 pin d-sub plug[1]) to your individual physical servers. You could then connect to your remote servers local TTY via the console server a little like jumping to remote servers via an SSH bastion. However it did sometimes require a little bit of prior configuration, depending on your distro[2].
This wasn't just limited to Linux either. It was a common UNIX trick :)
This is a bit of a lost art these days though. iLo, IPMI have replaced the need for serial. Then virtualisation and, to a lesser extent, containerisation have lowered the bar even further plus also moving the industry towards more ephemeral systems that can be destroyed and rebuilt automatically rather than the old habits of nursing failed hosts back to health.
[1] https://duckduckgo.com/?q=9+pin+d-sub+plug&t=newext&atb=v316...
[2] https://www.kernel.org/doc/html/v5.3/admin-guide/serial-cons... (a lot of distros at the time did ship a kernel with this support compiled in. I don't know how common it is now).
Re:An Ubuntu kernel bug causes container crashes
by jacquesm on Wednesday July 06, 2022 @05:40AM
(#31998692)
And quite a few implementations actually emulate the serial console allowing for the exact same access. (Serial Over Lan or SOL for short.)