Ask Your Question

Revision history [back]

click to hide/show revision 1
initial version

Quantum OVS multiple networks

Here is a question that I have not been able to find an answer to. I try to make the problem as clear as possible:

I have two servers: Server A and Server B. Server A installed using devstack runs all the services including Quantum with OVS. Server B is a Compute node only with Quantum OVS agent.

I create two networks: one for the Admin project (9.9.9.0/24) and one for the Demo project (9.9.8.0/24) .

Then I start creating VMs for each project which get created alternatively on Server A and Server B. After creating a few VMs I have the following:

Server A VMs: admin1, admin3, admin5, demo1, demo3, demo5 (all having correct IP like 9.9.9.2 and 9.9.8.2, etc) Server B VMs: admin2, admin4, admin6, demo2, demo4, demo6 (all having correct IP like 9.9.9.3 and 9.9.8.3, etc)

Now from VMs on each network I can ping other VMs on the same network. So far so good.

Then I try pining nodes on the other network and I notice the following:

From each VM on Server A I can also ping the VMs on Server B which are on the other network. For example from admin1, I can ping demo2, demo4, and demo6 even though I cannot ping demo1, demo3, and demo5.

Why? What am I doing wrong?

This is the traceroute from 9.9.9.2 on Server A to 9.9.8.4 on server B. The ping works while it should not.

% traceroute to 9.9.8.4 (9.9.8.4), 30 hops max, 46 byte packets 1 reserved-9-9-9-1.atlanta.ibm.com (9.9.9.1) 0.477 ms 0.183 ms 0.188 ms 2 9.9.8.4 (9.9.8.4) 0.988 ms 0.596 ms 0.522 ms

This is the traceroute from 9.9.9.2 on Server A to 9.9.8.5 on Server A. The ping does not work as expected: % traceroute to 9.9.8.5 (9.9.8.5), 30 hops max, 46 byte packets 1 reserved-9-9-9-1.atlanta.ibm.com (9.9.9.1) 0.444 ms 0.239 ms 0.223 ms 2 * * * 3 * * *

Here is the route table on Server A:

mb@sysnet45:~$ route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 9.2.156.65 0.0.0.0 UG 0 0 0 eth1 9.2.156.64 * 255.255.255.192 U 0 0 0 eth1 9.9.8.0 * 255.255.255.0 U 0 0 0 gw-f25ffc5e-d3 9.9.9.0 * 255.255.255.0 U 0 0 0 gw-e84cecf1-06 10.0.0.0 * 255.255.255.0 U 0 0 0 gw-9ad6270b-f7 192.168.1.0 * 255.255.255.0 U 0 0 0 eth0 192.168.122.0 * 255.255.255.0 U 0 0 0 virbr0

Here is the route table on Server B:

mb@sysnet43:~$ route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface default 9.2.156.65 0.0.0.0 UG 100 0 0 eth1 localnet * 255.255.255.192 U 0 0 0 eth1 192.168.1.0 * 255.255.255.0 U 0 0 0 eth0 192.168.122.0 * 255.255.255.0 U 0 0 0 virbr0