IP Allocation when moving KVM Virtual Machines

Submitted by HiedelbergiT on Wed, 12/23/2015 - 02:41

Hello, I have the following issue: 2 CentOS 7 KVM Hosts controlled by a Cloudmin Master. On the KVM Hosts are 2 Network Bridges "br10" and "br11" with different IP Ranges (IPv4 and IPv6) assigned. Prevent IP Spoofing is enabled.

Now what happens is that when I have a VM with only br10 network and move it everything works as it should.

However a VM connected to br11 works on both hosts when created. When I do a move to the other system the following happens

1) Allocate new IP address if neccessary is on

VM allocates a IP address from br10 network (should not do it) but keeps the IP address of the br11 network. So it becomes unreachable.

2) Allocate new IP address if neccessary is off

VM deletes the entry in the Ressource Limits Tab for the IPv4 address, but keeps entry for IPv6. So the machine becomes unreachable via IPv4. I need to readd the assigned IPv4 address to make it work again.

Thanks for any advice.

Status: 
Closed (fixed)

Comments

Submitted by JamieCameron on Thu, 12/24/2015 - 02:06

So in the case where moving a VM has problems, does it have IPs on both br10 and br11? And if so, do those bridges have the same allocation ranges on both the old and new host systems?

Submitted by HiedelbergiT on Mon, 12/28/2015 - 01:08

It has only IPs on br11. The allocation ranges are diffenrent on br10 and br11 but the same across the Host systems (Common IPv4 and IPv6 Pools)

Submitted by JamieCameron on Mon, 12/28/2015 - 15:20

Ok, I see the problem that causes the error in the second case, and will fix it in the next Cloudmin release.

For the first case, are you saying that the IP address on the VM gets allocated from the range assigned to br10, but the interface is still connected to br11?

Submitted by HiedelbergiT on Tue, 12/29/2015 - 01:06

Yes that is what im saying. But it should also not allocate a new IP address at all because the ranges are the same across both host systems.

Submitted by JamieCameron on Tue, 12/29/2015 - 12:29

Ok, I see the bug that causes this now - it will be fixed in the next Cloudmin release.

Submitted by HiedelbergiT on Wed, 12/30/2015 - 04:19

Thanks Jamie.

One last question: When is ETA für next cloudmin release?

Submitted by JamieCameron on Wed, 12/30/2015 - 12:34

A week or two - we haven't done a release for a while.