Difference between revisions of "LXC"

From CRIU
Jump to navigation Jump to search
(→‎Troubleshooting: use sub-sections)
(→‎See also: renamed to →‎External links: , formatting fix)
Line 59: Line 59:
 
CRIU doesn't yet support shared mountpoints as LXC does; make sure your rootfs is on a non-shared mount.
 
CRIU doesn't yet support shared mountpoints as LXC does; make sure your rootfs is on a non-shared mount.
  
== See also ==
+
== External links ==
  
* [https://www.youtube.com/watch?v=a9T2gcnQg2k&feature=youtu.be&t=18m8s The New New Thing: Turning Docker Tech into a Full Speed Hypervisor] - Talk of Tycho Andersen with demo of migration LXC container with Doom inside. [https://github.com/tych0/presentations/blob/master/ods2014.md Demo script]
+
* [https://www.youtube.com/watch?v=a9T2gcnQg2k&feature=youtu.be&t=18m8s The New New Thing: Turning Docker Tech into a Full Speed Hypervisor] - Talk of Tycho Andersen with demo of migration LXC container with Doom inside
 +
* [https://github.com/tych0/presentations/blob/master/ods2014.md Demo script]
  
 
[[Category: HOWTO]]
 
[[Category: HOWTO]]
 
[[Category: Live migration]]
 
[[Category: Live migration]]

Revision as of 19:16, 21 September 2016

Requirements

You should have built and installed a recent (>= 1.3.1) version of CRIU.

Checkpointing and restoring a container

LXC upstream has begun to integrate checkpoint/restore support through the lxc-checkpoint tool. This functionality has been in the recent released version of LXC---LXC 1.1.0 , you can install the LXC 1.1.0 or you can check out the development version on Ubuntu by doing:

sudo add-apt-repository ppa:ubuntu-lxc/daily
sudo apt-get update
sudo apt-get install lxc

Next, create a container:

sudo lxc-create -t ubuntu -n u1 -- -r trusty -a amd64

And add the following lines (as above) to its config:

cat | sudo tee -a /var/lib/lxc/u1/config << EOF
# hax for criu
lxc.console = none
lxc.tty = 0
lxc.cgroup.devices.deny = c 5:1 rwm
EOF

Finally, start, and checkpoint the container:

sudo lxc-start -n u1
sleep 5s  # let the container get to a more interesting state
sudo lxc-checkpoint -s -D /tmp/checkpoint -n u1

At this point, the container's state is stored in /tmp/checkpoint, and the filesystem is in /var/lib/lxc/u1/rootfs. You can restore the container by doing:

sudo lxc-checkpoint -r -D /tmp/checkpoint -n u1

And then, get your container's IP and ssh in:

ssh ubuntu@$(sudo lxc-info -i -H -n u1)

Troubleshooting

Error (mount.c:805): fusectl isn't empty: 8388625

Dumping of fuse filesystems is currently not supported. Empty the container's /sys/fs/fuse/connections and try again.

Error (mount.c:517): Mount 58 (master_id: 12 shared_id: 0) has unreachable sharing

CRIU doesn't yet support shared mountpoints as LXC does; make sure your rootfs is on a non-shared mount.

External links