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routeropenvswitchvlan

How to forward packets between VLANs on Open vSwitch router?


I'm trying to configure an OVS router. I want to achieve that, by adding flows on the OVS router, the devices connected with switch ports (port 2-5) can access to the internet, if the internet cable is inserted into the WAN port (port 1).

My VLAN configuration in file /etc/config/network of the OVS router is:

eth1.1: 0t, 2
eth1.2: 0t, 3
eth1.3: 0t, 4
eth1.4: 0t, 5
eth1.5: 1, 6

The output of ovs-vsctl show is:

root@OpenWrt:~# ovs-vsctl show
84d9ab2f-a3e6-46e3-874f-156ef975d673
Bridge "br0"
    Controller "tcp:<an IP address>"
        is_connected: true
    fail_mode: standalone
    Port "eth1.4"
        Interface "eth1.4"
    Port "eth1.2"
        Interface "eth1.2"
    Port "eth1.1"
        Interface "eth1.1"
    Port "br0"
        Interface "br0"
            type: internal
    Port "eth1.3"
        Interface "eth1.3"

The truncated output of ifconfig is:

br0: 192.168.3.1 
eth0: 192.168.0.105 (There is another home router)
eth1, eth1.1-1.4

As the subnet provides IP prefix of 192.168.3.* and the router itself is assigned IP of 192.168.0., I wonder if it's helpful to add a flow to forward packets from 192.168.3. to 192.168.0.104.

So is it correct if I suppose, a machine with IP 192.168.3.10, for example, it wants to make query to google, the path should be 192.168.3.10->192.168.0.105->192.168.0.1(home router)->outside?

This is to build a flow based on Layer3. But I'm wondering if I can build flows between VLANs? According to my configuration, WAN port is port1, belongs to VLAN 5. Do you think is viable to add flows bidirectionally from VLAN 1 (machine connected) to VLAN 5 and from VLAN 5 to VLAN 1? If so, is there any examples I can flow please?

Another detail. The output of ifconfig shows eth0 interface was assigned IP 192.168.0.105, which means it's connected with my home router (192.168.0.1). So do I need to forward packets between these to IP addresses?

I really appreciate any help.


Solution

  • I have solved this problem. Following is the solution.

    The main idea is to build a linux bridge connected with OVS bridge, when I need the VLANs to be able talking with outside internet. I can use brctl to operate linux bridge. Firstly I tried:

    brctl addbr br-lan
    brctl addif br-lan br0
    

    Then all the machine can access to the internet. But unfortunately, only for couple minutes. After that, the router collapsed. I could not access to the OVS router anymore unless I reset it. That could be caused by the incorrect bridge configuration. I tried many ways and finally this one works:

    brctl addbr br-lan
    ifconfig br-lan 192.168.3.1
    brctl addif br-lan br0
    ifconfig br0 0.0.0.0
    

    I considered linux bridge br-lan should be originally connected with eth0 (wan). And as I know, br0 could means 'local', with IP address 192.168.3.1. All VLANs talk with this IP address. If I move 'local' to linux bridge which connected with wan port, it should work.

    Thanks for everybody who viewed and tried to help me!