No traffic on br-tun

asked 2014-03-02 20:20:56 -0500

xionglingfeng gravatar image

updated 2014-03-02 20:21:55 -0500

I configured one network node and one compute node on a Xen based server. When a VM is bring up, it cannot get a IP address from DHCP. I tried to set its IP address manually and ping the gateway, of course, all packets are timed out.

In computer node, I run tcpdump to capture packets. For br-int, I do captured packets from client

xxxx@os-compute:~$ sudo tcpdump -i br-int

tcpdump: WARNING: br-int: no IPv4 address assigned

tcpdump: verbose output suppressed, use -v or -vv for full protocol decode

listening on br-int, link-type EN10MB (Ethernet), capture size 65535 bytes

22:48:56.730834 ARP, Request who-has tell , length 28

However, in br-tun, there is no traffic.

Anyone can help me on this? Thanks.

The configuration of OpenVSwitch is listed below:

xxxx@os-compute:~$ sudo ovs-vsctl show


Bridge br-int

    Port br-int

        Interface br-int

            type: internal

    Port "eth3"

        Interface "eth3"

    Port patch-tun

        Interface patch-tun

            type: patch

            options: {peer=patch-int}

Bridge br-tun

    Port "vxlan-1"

        Interface "vxlan-1"

            type: vxlan

            options: {in_key=flow, local_ip="", out_key=flow, remote_ip=""}

    Port br-tun

        Interface br-tun

            type: internal

    Port patch-int

        Interface patch-int

            type: patch

            options: {peer=patch-tun}

ovs_version: "1.10.2"
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Are you using VXLan ? Just run 'sudo udhcpc' from vm and till which point packets are coming ? Run tcpdump -n -i <interface> command. See whether DHCP requests are coming at every interface point.

dheeru gravatar imagedheeru ( 2014-03-02 23:04:06 -0500 )edit

I too have the same problem it is reaching hust br-int not br-tun. please help

fresher gravatar imagefresher ( 2015-01-01 01:28:30 -0500 )edit

check ovs-ofctl dump-flows br-tun to check if the amount of packets being accepted is increasing or not. Tcpdump -i br-tun might not work for several reasons.

rever gravatar imagerever ( 2015-02-04 09:44:14 -0500 )edit