editing files in lxc container over tramp/ssh frequently hangs

[Erno Kuusela]

I have a vanilla LXD setup, configured with instructions from https://www.zenly.co.uk/lxd-on-ubuntu-xenial-16-04/ - so both host and container are Ubuntu 16.04.

The problem is like the summary says. A workaround that fixes (or makes less frequent?) the hangs: turn off tramp's use of the ssh ControlMaster feature. I did this via customize, toggled the "Tramp Use Ssh Controlmaster Options" setting to off.

When the hang happens, the minibuffer status is saying "Tramp: Found remote shell prompt on <hostname>".
I can get out of the hang by hitting C-g 3 times but that tends to break whatever action Emacs was doing over tramp.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: emacs24 24.5+1-6ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-45.66-generic 4.4.21
Uname: Linux 4.4.0-45-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Oct 26 09:49:51 2016
InstallationDate: Installed on 2016-10-13 (12 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
SourcePackage: emacs24
UpgradeStatus: No upgrade log present (probably fresh install)