How to disconnect from lxc-console

Question

I'm working with lxc in Ubuntu 12.04, and it's really great. However, I am unable to disconnect from a lxc-console session after I've connected. I read somewhere that Ctrl-aq will disconnect me from the console but it doesn't seem to work.

Should I be running lxc-console via screen instead?

Solution 1

Yes, Ctrl-aq, should work by default, however no, lxc-console does not actually use screen to accomplish its console behavior. In fact, you might be encountering a conflict if you are using screen since it also uses Ctrl-a as a prefix. If you're inside screen but don't realize it then you'll need to type Ctrl-a a q since the default behavior of screen is that you have to type Ctrl-a a to actually send ^a to the shell running inside of it. You can change the prefix for escape by passing the -e or --escape=PREFIX option to lxc-console.

Also, it appears there may be a bug in lxc-start so that if it immediately goes into console mode when you start the container you can't using Ctrl-a q to escape-- in fact, all the control characters seem to be screwed up and print to the screen instead of behaving the way you expect. One workaround is to run it with the -d or --daemon option so that it doesn't immediately start a console, and the connect to it by hand:

lxc-start -d -n container-name
lxc-console -n container-name

Solution 2

What I did to stop the container

1. Open a new session.
2. Login as root.
3. Check the container status.
4. lxc-stop -n <name of the container>

This will stop the container.

Comments

[Martin Serrano]

you can also do an lxc-stop from another shell

[robbyt]

No, this does not work. I've been using screen so that I can disconnect from lxc-console. Also, the link that you posted does not have any information about this problem.

[El Yobo]

"Detach screen: C-a d or C-a C-d" - help.ubuntu.com/community/LXC#Mini_screen_how-to; not sure what to do if that's not working.

[aculich]

@ElYobo No, lxc-console does not actually use screen, it just has similar behavior and by default actually uses a key that conflicts with screen's as described here.

[Jay Taylor]

<kbd>Ctrl-a q</kdb> does not have any effect on a connected console with lxc version 0.9.0

[Florian Heigl]

if the lxc devs should ever wonder why docker had a billion times higher adoption, this bug is one of the main reasons.

[AlpSenel]

@FlorianHeigl While I agree with your sentiment about this bug being ugly, the true reasons for that are attitudes: bugs.debian.org/cgi-bin/bugreport.cgi?bug=768073 access.redhat.com/articles/1365153 access.redhat.com/discussions/2772171 (and numerous other occasions where RedHat responds to "LX(C|D)?" with "No, Docker!" (note that these are top Google results for "LXD Debian", and "LXD Redhat queries").