Page History

...

Following steps need to be performed before adding installing agent on LXC host to management server

• Fix cgroup co-mounting error in RHEL7: 
  • When cpu,cpuacct are co-mounted, libvirt fails to create containers. This issue is fixed in later versions of libvirt. For libvirt 1.1.1 which comes with RHEL7, below work-around is required
  • Rhel7 Initial RAM disk (initrd) uses systemd. Any changes made to cgroup will be lost after reboot.  So rebuild the initrd

  • Set JoinControllers to empty string in /etc/systemd/system.conf. Empty string ensures that systemd mounts all controllers in separate hierarchies

JoinControllers=

• • Backup initrd.

cp /boot/initramfs-$(uname -r).img /boot/initramfs-$(uname -r).img.bak

• • Rebuild initrd

dracut -f

• • Reboot host

• on RHEL7, NetworkManager resets mac address of the Vm: CLOUDSTACK-7515
• Disable NetworkManager  to work-around this issue:
  • service NetworkManager stop
  • chkconfig NetworkManager off
ToDo: cloudstack-setup-agent script should check if cgroup is properly mounted and raise exception if cgroups are not properly configured

Versions

LXC version 1.0

Libvirt Version 1.21.1

Open Issues

LXC hosts need not be hvm enabled. So, a VM can also act as a host for LXC conatiners. Currently, cloudstack doesn't allow hosts which are not hvm enabled. This check has to be relaxed for LXC.

...