Ask Your Question

Revision history [back]

TCP traffic and OpenvSwitch

I'm having an issue with OpenvSwitch whereby I have ping traffic passing but am unable to pass any tcp traffic (e.g. SSH).

I've attached two pcap files which show the following:

  • Host 1 (10.2.1.1): ping -c 3 10.2.2.1 && ssh 10.2.2.1
  • Brief Pause
  • Host 2 (10.2.2.1): ping -c 3 10.2.1.1 && ssh 10.2.1.1

As you can see, ping passes but ssh doesn't.

This seems to be in contradiction to my OVS flow config which is simple as as follows (these are the only flows configured on this OVS bridge) :

ovs-ofctl add-flow lon2local dl_type=0x800,nw_src=10.2.0.0/20,nw_dst=10.2.1.0/24,actions=output:73
ovs-ofctl add-flow lon2local dl_type=0x800,nw_src=10.2.0.0/20,nw_dst=10.2.2.0/24,actions=output:76
ovs-ofctl add-flow lon2local arp,nw_dst=10.2.1.0/24,actions=output:73
ovs-ofctl add-flow lon2local arp,nw_dst=10.2.2.0/24,actions=output:76

Hopefully somebody here is familiar with OVS, has seen these sort of flow issues before and can suggest how to fix it ?

(Edit, I see as a newbie here I am unable to attach files - perhaps the mods can suggest how I can best share files ?)

TCP traffic and OpenvSwitch

I'm having an issue with OpenvSwitch whereby I have ping traffic passing but am unable to pass any tcp traffic (e.g. SSH).

I've attached two pcap files which show the following:

  • Host 1 (10.2.1.1): ping -c 3 10.2.2.1 && ssh 10.2.2.1
  • Brief Pause
  • Host 2 (10.2.2.1): ping -c 3 10.2.1.1 && ssh 10.2.1.1

As you can see, ping passes but ssh doesn't.

This seems to be in contradiction to my OVS flow config which is simple as as follows (these are the only flows configured on this OVS bridge) :

ovs-ofctl add-flow lon2local dl_type=0x800,nw_src=10.2.0.0/20,nw_dst=10.2.1.0/24,actions=output:73
ovs-ofctl add-flow lon2local dl_type=0x800,nw_src=10.2.0.0/20,nw_dst=10.2.2.0/24,actions=output:76
ovs-ofctl add-flow lon2local arp,nw_dst=10.2.1.0/24,actions=output:73
ovs-ofctl add-flow lon2local arp,nw_dst=10.2.2.0/24,actions=output:76

Hopefully somebody here is familiar with OVS, has seen these sort of flow issues before and can suggest how to fix it ?

(Edit, I see as a newbie here I am unable to attach files - perhaps the mods can suggest how I can best share files ?)PCAPS: https://send.tresorit.com/a#_vfy8aLsUmF4YzbkmD5pOw