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An Ubuntu kernel bug causes container crashes

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41–50 of 133 posts

Re: An Ubuntu kernel bug causes container crashes

#41
post #33

Earlier quoted context omitted.

Complexity is just another part of natural systems. It's not something to be avoided for it's own sake, in as much as we should avoid having eyeballs, because they are crazily complex. Yet we tend to like ours and find them worth whatever cost they incur. The emergent behavior of containerization has had an overall positive effect, even if it has annoying costs.

For the end user there is no positive effect. Many websites were better in 2005 and had greater uptime. They were also better organized. Ebay and Amazon were leaner and more pleasant to use.

> Many websites were better in 2005 and had greater uptime.

Citation needed. There were a lot less sites, maintenance windows in the hours weren't uncommon, there was no security to speak of (SQL injections, no SSL/TLS, etc.), and sites could do maybe 1% of what today's sites can (not saying that all of it is good or necessary, bit i quite like a non-insignificant amount of those new features like native video, audio, graphics, dynamism, etc.).

Re: An Ubuntu kernel bug causes container crashes

#42
post #21
post #3

This was even worse than the headline made it sound. If you had `unattended-upgrades` running and had the "automatic reboot" option enabled, then all your Ubuntu 20.04 servers running Docker would reboot themselves and not come back up. First, the bug was in a security branch. Second, it wasn't just the containers that crashed. If you booted containers on boot via Docker, then the host OS kernel-panicked and crashed…

Wouldn't rollback of kernel be a choice in grub menu? It's pretty standard for all distros to have that choice.

That usually requires physical access to the server to select it during boot.

Re: An Ubuntu kernel bug causes container crashes

#43
post #21

Earlier quoted context omitted.

Wouldn't rollback of kernel be a choice in grub menu? It's pretty standard for all distros to have that choice.

That usually requires physical access to the server to select it during boot.

Or a real server with Lights Out Management.

Re: An Ubuntu kernel bug causes container crashes

#45
post #9

Wow, another buggy Ubuntu patch breaks something. Why don’t they just stick to what’s upstream?

Yeah, I don't really get why they don't use the stable kernel releases, of which there are many, rather than rolling their own.

Seems like every department at canonical needs to learn this on their own.

After all, they reinvented everything from DE to init system at least once in past.

(They also have their own containers, LXD. I actually really like that one, please keep working on that canonical)

Re: An Ubuntu kernel bug causes container crashes

#46
post #21

Earlier quoted context omitted.

Wouldn't rollback of kernel be a choice in grub menu? It's pretty standard for all distros to have that choice.

That usually requires physical access to the server to select it during boot.

Not necessarily. With good timing and some luck, you can connect the serial/"recovery" console before GRUB's timeout ends and either change the running kernel or add the `systemd.mask=docker.service` boot parameter to prevent Docker from starting.

Re: An Ubuntu kernel bug causes container crashes

#47
post #46

Earlier quoted context omitted.

That usually requires physical access to the server to select it during boot.

Not necessarily. With good timing and some luck, you can connect the serial/"recovery" console before GRUB's timeout ends and either change the running kernel or add the `systemd.mask=docker.service` boot parameter to prevent Docker from starting.

Sounds like a VM and not a physical server.

Re: An Ubuntu kernel bug causes container crashes

#48

Earlier quoted context omitted.

That usually requires physical access to the server to select it during boot.

Or a real server with Lights Out Management.

That’s why “usually” is in the sentence. :)

Most smaller teams usually don’t prioritize physical access — they usually only need it for one-off events. While this would be a one-off event, it would be one that affects many servers.

Re: An Ubuntu kernel bug causes container crashes

#50
post #27
post #17

Earlier quoted context omitted.

This is not a docker bug, it is a kernel bug. It could be triggered by other complex applications that use kernel container features.

Or it could not be triggered if you don't use containers.

Would it have occurred on Podman as well?
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