X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=FAQ;h=c266b7bfb7db3ef79c4361d7eecb7ce4b54179af;hb=42d5dd9595cce35a8825a20be7d71a3a8f6f5640;hp=186f3ac4a1e64bb947f75522205b37a4fc4f4f6b;hpb=0f5edef014cc4ca701dab6006e9f59d24adad266;p=sliver-openvswitch.git diff --git a/FAQ b/FAQ index 186f3ac4a..c266b7bfb 100644 --- a/FAQ +++ b/FAQ @@ -325,6 +325,43 @@ A: No. ERSPAN is an undocumented proprietary protocol. As an alternative, Open vSwitch supports mirroring to a GRE tunnel (see above). +Q: How do I connect two bridges? + +A: First, why do you want to do this? Two connected bridges are not + much different from a single bridge, so you might as well just have + a single bridge with all your ports on it. + + If you still want to connect two bridges, you can use a pair of + patch ports. The following example creates bridges br0 and br1, + adds eth0 and tap0 to br0, adds tap1 to br1, and then connects br0 + and br1 with a pair of patch ports. + + ovs-vsctl add-br br0 + ovs-vsctl add-port br0 eth0 + ovs-vsctl add-port br0 tap0 + ovs-vsctl add-br br1 + ovs-vsctl add-port br1 tap1 + ovs-vsctl \ + -- add-port br0 patch0 \ + -- set interface patch0 type=patch options:peer=patch1 \ + -- add-port br1 patch1 \ + -- set interface patch1 type=patch options:peer=patch0 + + Bridges connected with patch ports are much like a single bridge. + For instance, if the example above also added eth1 to br1, and both + eth0 and eth1 happened to be connected to the same next-hop switch, + then you could loop your network just as you would if you added + eth0 and eth1 to the same bridge (see the "Configuration Problems" + section below for more information). + + If you are using Open vSwitch 1.9 or an earlier version, then you + need to be using the kernel module bundled with Open vSwitch rather + than the one that is integrated into Linux 3.3 and later, because + Open vSwitch 1.9 and earlier versions need kernel support for patch + ports. This also means that in Open vSwitch 1.9 and earlier, patch + ports will not work with the userspace datapath, only with the + kernel module. + Q: Why are there so many different ways to dump flows? A: Open vSwitch uses different kinds of flows for different purposes: @@ -779,6 +816,21 @@ A: It is to be expected that the VMs can't access each other. VLANs the machines you are trying to access are not on VLAN 9 (or 10) and that the Internet is not available on VLAN 9 (or 10). +Q: I added a pair of VMs on the same VLAN, like this: + + ovs-vsctl add-br br0 + ovs-vsctl add-port br0 eth0 + ovs-vsctl add-port br0 tap0 tag=9 + ovs-vsctl add-port br0 tap1 tag=9 + + The VMs can access each other, but not the external network or the + Internet. + +A: It seems likely that the machines you are trying to access in the + external network are not on VLAN 9 and that the Internet is not + available on VLAN 9. Also, ensure VLAN 9 is set up as an allowed + trunk VLAN on the upstream switch port to which eth0 is connected. + Q: Can I configure an IP address on a VLAN? A: Yes. Use an "internal port" configured as an access port. For