Bug 33694 - Virtualization bridges should be configured in UCS network setup
Virtualization bridges should be configured in UCS network setup
Product: UCS
Classification: Unclassified
Component: Virtualization - UVMM
UCS 3.0
Other Linux
: P5 normal (vote)
: UCS 4.0
Assigned To: Philipp Hahn
Erik Damrose
: interim-3
Depends on:
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Reported: 2013-12-10 09:58 CET by Moritz Muehlenhoff
Modified: 2014-11-26 06:54 CET (History)
3 users (show)

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Setup empty bridge (3.44 KB, patch)
2014-11-05 21:11 CET, Philipp Hahn
Details | Diff

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Description Moritz Muehlenhoff univentionstaff 2013-12-10 09:58:12 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.
Comment 1 Philipp Hahn univentionstaff 2014-01-31 10:55:49 CET
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.
Comment 2 Janis Meybohm univentionstaff 2014-08-21 16:12:37 CEST
Requested by customer via Ticket#: 2014082121000391
Comment 3 Stefan Gohmann univentionstaff 2014-08-29 10:06:09 CEST
The current implementation breaks KVM on a DHCP server.
Comment 4 Philipp Hahn univentionstaff 2014-10-10 11:37:58 CEST
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.
Comment 5 Philipp Hahn univentionstaff 2014-10-17 17:31:40 CEST
r54614 | Bug #33694 network: Document bridge changes
 WIP document changs
Comment 6 Philipp Hahn univentionstaff 2014-10-20 10:01:23 CEST
(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

Comment 7 Philipp Hahn univentionstaff 2014-10-20 16:34:14 CEST
(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
Comment 8 Erik Damrose univentionstaff 2014-11-05 18:10:19 CET
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.
Comment 9 Philipp Hahn univentionstaff 2014-11-05 18:48:03 CET
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
Comment 10 Philipp Hahn univentionstaff 2014-11-05 21:11:34 CET
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.
Comment 11 Philipp Hahn univentionstaff 2014-11-07 19:58:47 CET
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

Package: univention-virtual-machine-manager-node
Version: 3.0.3-1.84.201411071940
Branch: ucs_4.0-0
Comment 12 Erik Damrose univentionstaff 2014-11-13 16:08:02 CET
Verified: Works for new installations and for Updated systems
Comment 13 Stefan Gohmann univentionstaff 2014-11-26 06:54:28 CET
UCS 4.0-0 has been released:

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