For the better part of the last half year, I’ve been trying to run virtual networks on a laptop which constantly moves from one WiFi network to another. Not surprisingly, I’ve been using Network Manager, but because currently Network Manager does not support managing virtual devices like br and tap, it’s not possible to create/destroy/manage/troubleshoot issues with these virtual devices unless I switch to “Classical ifup/ifdown”
And, the virtual networks can be very flaky at times, eg. today although the virbr0 created by libvirt is configured to autostart, it didn’t.
I’m also troubleshooting why although Guests can typically connect to the Internet, it’s not always possible for the Host to access the Guest with a “no route to host” error despite a proper entry in the routing table(eliminated the usual stuff like FW issues, verified running services)
Although I’ve prepared for a WiFi life without Network Manager (verifying wpa_gui is installed and refreshing on latest info about wpa_supplicant and iw), am looking for a last stab if anyone is using Network Manager regularly and is able to troubleshoot virtual networking issues. Am looking mainly for non-VMware experiences, my experience is that one of the things that VMware does superlatively is create and manage stable and reliable networking.
AFAIK VMware is unique in the networking objects it creates, all other virtualization technologies (eg Virtual Box, Xen, KVM, QEMU, UML) build on the same virtual networking objects.
I did a dry run.
Without Network Manager running, wpa_gui launched but did not seem to connect to wpa_supplicant correct.
I was able to find the YAST “classical ifup/ifdown” tool to configure wireless, was impressed that it provides basic functionality but does not look like a tool to be used when changing between numerous wireless networks. Might be OK in a single location like an office.
Also found various existing virtual network devices did not work as expected.
In the interests of time,
I’m now considering continuing to use Network Manager, but manage virtual devices as much as possible using the brctl command in a console.
Still interested in any experiences others might have had re: my original post.
For those who come across this desired setup later (WiFi, KVM/Xen/LXC virtualization) I think I’ve finally put together the “magic combination” (for now).
The minor gotcha is that <all> documentation everywhere only describes creating virtual bridge devices using IFUP/IFDOWN, although I’ve found that’s possible the networks based on those bridges have been unstable for unknown reasons (could be User error) and it’s very inconvenient to switch back and forth between “Classical” and NM.
Use this Network Manager, understanding it has no support for displaying and managing virtual devices despite creating and using TAP devices for tunneling.
Install and use libvirt tools (vm manager, vm install, etc)
The **virsh **command line tool if necessary
The standard brctl command can be used to display (depending on the technology, not always create).
Sometime when I get some time, I’ll create a Wiki describing how this should be setup most easily, complete with modifying firewall and net filter settings.
Until then, either post to the Forums, but know that this combination seems to work when setup properly.
TSU