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?

I have the same issue. If you start a container forgetting the "-d" parameter, there is no way out. Ctrl a q has no effect. The only solution I have found is to login to the console, and do "sudo poweroff", that gets you out. — eos, Jun 06 '15 at 22:03

aculich · Accepted Answer · 2012-10-16T08:37:51.663

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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

edited Oct 16 '12 at 08:37

answered Oct 16 '12 at 08:20

aculich

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Ctrl-a q does not have any effect on a connected console with lxc version 0.9.0 – Jay Taylor Aug 30 '13 at 20:43
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if the lxc devs should ever wonder why docker had a billion times higher adoption, this bug is one of the main reasons. – Florian Heigl Aug 14 '16 at 20:43
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@FlorianHeigl While I agree with your sentiment about this bug being ugly, the true reasons for that are attitudes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=768073 https://access.redhat.com/articles/1365153 https://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"). – Bojan Markovic Feb 27 '18 at 15:51

score 3 · Answer 2 · edited Aug 05 '16 at 14:51

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What I did to stop the container

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

This will stop the container.

edited Aug 05 '16 at 14:51

HBruijn

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answered Aug 05 '16 at 13:49

Sreenivas

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score 0 · Answer 3 · answered Jul 15 '12 at 06:53

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Doesn't it connect via screen? Ctrl-a d should get you out of it.

The Ubuntu LXC page has more information.

answered Jul 15 '12 at 06:53

El Yobo

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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. – robbyt Aug 06 '12 at 03:02
"Detach screen: C-a d or C-a C-d" - https://help.ubuntu.com/community/LXC#Mini_screen_how-to; not sure what to do if that's not working. – El Yobo Aug 06 '12 at 23:34
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@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](http://serverfault.com/a/438824/93109). – aculich Oct 16 '12 at 08:21

score 0 · Answer 4 · answered May 17 '15 at 15:09

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An alternative way to login is to just do ssh <ip> instaed of using lxc-console. You could use start it as daemon using lxc-start -d -n <name> and then login using console to get the IP for the first time.

answered May 17 '15 at 15:09

Nishant

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score 0 · Answer 5 · answered Sep 19 '16 at 02:19

I had a similar issue when working with my Trusty LXC in Xenial-host and after starting the container with lxc-start -F -n CN couldn't get out and back to host when logged out from the container. Also the sudo lxc-ls -fin the host hanged and none of the lxc-stopcommands with -k or -W or --no-lock options worked, so I eventually kill -9'd the container process which worked but afterwards starting the container with lxc-start or lxc-attachdo not work properly, but display errors about lxc_cgfsng and not finding the init pid etc.

See more here: https://github.com/lxc/lxc/issues/1195

score -6 · Answer 6 · answered Oct 13 '12 at 15:30

When you are done working with some application you can usually terminate it witch CTR+C. If that doesn't do the trick, there is always the quit command: CTRL+.

CTRL+D, on the other hand means "END OF FILE", and works usually to stop some program from reading the keyboard. You can log out of regular shell with CTRL+D.

How to disconnect from lxc-console

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