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2017-05-11 02:20:32 -0500 answered a question (Mitaka, SR-IOV) Possible to mix Flat and VXLAN nets on same VM?

Answering my own question but; yes it is possible and the problem was the we had gateways configured for the flat subnets. If the gateways are removed then everything works as it should.

So essentially the network configuration ended up as: - 1 "Management" VXLAN network - 1 flat network representing the fast NIC, with DHCP disabled and gateway disabled

2017-05-11 02:17:11 -0500 commented question (Mitaka, SR-IOV) Possible to mix Flat and VXLAN nets on same VM?

We are using Fuel for our deployment so that takes care of the VXLAN configuration for the most part. But as it turned out, it was a silly problem where I just had to remove the gateway from the flat subnets; without the GW everything works like a charm.

2017-05-10 11:09:33 -0500 asked a question (Mitaka, SR-IOV) Possible to mix Flat and VXLAN nets on same VM?

We have a setup where we have two nodes directly connected to each other via high-speed NICs, and then a normal connection to the switch. We have SR-IOV configured for the fast NICs.

What I want is to use a flat network for SR-IOV, and then a VXLAN configuration for the "management" and internet connection using the normal NIC that's connected to the switch. So right now there are two networks: flat_1 and admin_internal_net.

I've created a VM with an IP from an SR-IOV port (--nic port-id=...) and an IP from admin_internal_net (--nic net-id=...) and I can connect to the VM through the flat network, but if I add a floating ip and try to ping that it does not work and the VM does not have an internet connection. Creating a VM with only an IP from admin_internal_net can be assigned a floating ip as usual.

So my question is, should this be possible, and if it is, is there something additional that needs to be configured somewhere for these two network types to be mixed?

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2017-03-23 23:45:15 -0500 asked a question neutron/ovs intermittent network failures

We're having some very strange networking issues. After a fresh install of OpenStack (using Fuel) everything seems to work alright for a couple of weeks. After running for a while, however, new instances will randomly fail to get an IP and after a while longer no instance will have any connectivity. Rebooting the servers sometimes helps, sometimes not (as I write this I've just rebooted into a "working" state).

Using tcdump I've seen that the dhcp packet arrives on the "tap" interface of the VM on the compute node but then it stops there and never reaches the physical interface -- so I'm guessing the problem lies here but I have no idea how/why.

I've been trying to compare the different outputs from ovs commands/logs from a working/non-working case but I can't really see any difference.

How can I go about troubleshooting this issue? What might actually cause the packets from not going past the bridge?

Currently we have a small setup with one controller node and one compute node, and we use vxlan for tunneling. Example output from "ovs-vsctl show" (not sure what else might be of interest):

root@node-13:~# ovs-vsctl show
fb7a1361-742a-4389-bc8c-c05b285a6ff6
    Manager "tcp:192.168.3.3:6640"
        is_connected: true
    Bridge br-ex
        Port "p_aec4d661-0"
            Interface "p_aec4d661-0"
                type: internal
        Port br-ex
            Interface br-ex
                type: internal
    Bridge br-int
        Controller "tcp:192.168.3.3:6653"
            is_connected: true
        fail_mode: secure
        Port "tap5bab7f58-46"
            Interface "tap5bab7f58-46"
        Port "vxlan-192.168.16.2"
            Interface "vxlan-192.168.16.2"
                type: vxlan
                options: {key=flow, local_ip="192.168.16.3", remote_ip="192.168.16.2"}
        Port "tap184ce9d7-47"
            Interface "tap184ce9d7-47"
        Port "tap87de89b5-22"
            Interface "tap87de89b5-22"
        Port "tap962f2f6d-09"
            Interface "tap962f2f6d-09"
        Port br-int
            Interface br-int
                type: internal
        Port "tape4f821b8-9b"
            Interface "tape4f821b8-9b"
    ovs_version: "2.5.90"