Univention Bugzilla – Bug 33694
Virtualization bridges should be configured in UCS network setup
Last modified: 2014-11-26 06:54:28 CET
KVM and Xen configure network bridges in their init scripts. If the network configuration wizard is run on such a system, a warning message is displayed, which redirects to http://docs.univention.de/computers-3.2.html: | UCS Virtual Machine Manager normally replaces eth0 with a bridge interface to | connect virtual machines to a network. This was achieved by two init scripts | renaming the physical interface eth0 to peth0 and creating a bridge called | eth0, into which the physical interface was connected. | | If you configure your own bridges, bonds or VLANs using the UMC or the | Univention Configuration Registry variables described above you need to | deactivate these scripts by setting the following UCR variables: This is complex and error-prone for the user. For new UVMM installations the bridges should be configured through the UCR network interface settings instead of the custom KVM/Xen bridge scripts.
libvirt provides a hook mechanism <http://libvirt.org/hooks.html#qemu>, which could be used to rewrite legacy "eth0" bridges into a new "br0" using the "/etc/libvirt/hooks/qemu guest_name migrate begin -" hook.
Requested by customer via Ticket#: 2014082121000391
The current implementation breaks KVM on a DHCP server.
For new UCS-4 installations the script will be disabled. For updates we will keep the old logic. For UCS-4.x we will provide a documentation on how to the script and migrate existing VMs to the new setup.
r54614 | Bug #33694 network: Document bridge changes WIP document changs
(In reply to Philipp Hahn from comment #4) > For UCS-4.x we will provide a documentation on how to the script and migrate > existing VMs to the new setup. r54635 | Bug #33694 network: Document bridge changes <http://jenkins.knut.univention.de:8080/job/UCS-4.0/job/UCS-4.0-0/job/Handbook%20Extended/lastSuccessfulBuild/artifact/webroot/uvmm-4.0.html#uvmmext:kvm>
(In reply to Philipp Hahn from comment #4) > For new UCS-4 installations the script will be disabled. > For updates we will keep the old logic. r54669 | Bug #33694 KVM: Disable bridge creation by default Also follow rename of /etc/init.d/libvirt{-bin,d} Package: univention-virtual-machine-manager-node Version: 3.0.2-1.81.201410201628 Branch: ucs_4.0-0
Reopen: On updated UCS systems the bridge configuration does not apply successfully, leaving the system without network access. Philipp and i just debugged it, the -node-kvm initscript has to be adapted.
r55401 | Bug #33694 KVM: Adapt bridge transfer to ifupdown change ifupdown-0.7~alpha2 switch from using "ifconfig" to "iproute". Package: univention-virtual-machine-manager-node Version: 3.0.2-3.83.201411051836 Branch: ucs_4.0-0
Created attachment 6310 [details] Setup empty bridge RFC: Installing a new UCS-4 virtualization server currently creates no bridge, but "br0" is configured in the profiles. This leads to the unfortunate situation, where VMs can be defined, but not started. We should at least setup an empty bridge "br0" which can be used for inter-VM communication until an ethernet interface is added manually.
r55536 | Bug #33694 UVMM: Setup empty bridge There's now a script /usr/lib/univention-virtual-machine-manager-node-kvm/ucs-kvm-setup-bridge, which is called from postinst and creates a network bridge using the default interface: UCRV uvmm/kvm/bridge/interface, interface used for default routing UCRV interfaces/primary 'eth0' Package: univention-virtual-machine-manager-node Version: 3.0.3-1.84.201411071940 Branch: ucs_4.0-0
Verified: Works for new installations and for Updated systems
UCS 4.0-0 has been released: http://docs.univention.de/release-notes-4.0-0-en.html http://docs.univention.de/release-notes-4.0-0-de.html If this error occurs again, please use "Clone This Bug".