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> <i>Add it to the possible wish list along with the MAC address
prefix</i>
<br>
<br>
If there is interest in an official LXC vendor MAC address
prefix, I'd like to call your attention to this Linux kernel bug:<br>
<br>
<a class="moz-txt-link-freetext" href="https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/584048">https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/584048</a><br>
<a class="moz-txt-link-freetext" href="https://www.redhat.com/archives/libvir-list/2010-July/msg00450.html">https://www.redhat.com/archives/libvir-list/2010-July/msg00450.html</a><br>
<br>
These bug reports are for KVM with bridging, however, I have
seen the same symptom using LXC. The symptom is that the network
bridge goes dead for several seconds when starting or stopping
containers. The root of the issue is in the Linux kernel, and how
it handles the MAC address of bridges (and bond interfaces, too). <br>
<br>
In summary, the MAC prefix can't be arbitrary, because a low MAC
vendor prefix causes a short-term network blackout on the bridge
device when starting or stopping LXC containers, or KVM/qemu VMs, or
any other environment using non-physical interfaces. The blackout
is (apparently) caused by the bridge changing its MAC address.<br>
<br>
I have added a workaround to my script for this bug (see Comment
#60 in Launchpad, above). According to Serge Hallyn: "That it is a
general bridge property is indeed known. The fix in this bug is,
like your script, simply working around that fact."<br>
<br>
<br>
Thank You,<br>
Derek Simkowiak<br>
<a class="moz-txt-link-abbreviated" href="mailto:derek@simkowiak.net">derek@simkowiak.net</a><br>
<br>
On 10/11/2011 06:08 AM, Brian K. White wrote:
<blockquote cite="mid:4E943FD0.5060405@aljex.com" type="cite">
<pre wrap="">That's a pretty substantial reduction. Add it to the possible wish list
along with the MAC address prefix. Sadly I never finished the research
to get that. The $600 is easy, the time to figure out what you're
supposed to do is not ;)
</pre>
</blockquote>
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