netlink-socket: Adapt to Windows and MSVC.

[cascardo/ovs.git] / FAQ

diff --git a/FAQ b/FAQ
index 7ef7eb4..3470983 100644 (file)
--- a/FAQ
+++ b/FAQ
@@ -190,6 +190,27 @@ A: The kernel module in upstream Linux does not include support for
    Linux release or using the kernel module paired with the userspace
    distribution.
 
+Q: Why do tunnels not work when using a kernel module other than the
+   one packaged with Open vSwitch?
+
+A: Support for tunnels was added to the upstream Linux kernel module
+   after the rest of Open vSwitch. As a result, some kernels may contain
+   support for Open vSwitch but not tunnels. The minimum kernel version
+   that supports each tunnel protocol is:
+
+   Protocol    Linux Kernel
+   --------    ------------
+     GRE           3.11
+     VXLAN         3.12
+     LISP      <not upstream>
+
+   If you are using a version of the kernel that is older than the one
+   listed above, it is still possible to use that tunnel protocol. However,
+   you must compile and install the kernel module included with the Open
+   vSwitch distribution rather than the one on your machine. If problems
+   persist after doing this, check to make sure that the module that is
+   loaded is the one you expect.
+
 Q: What features are not available when using the userspace datapath?
 
 A: Tunnel virtual ports are not supported, as described in the
@@ -499,6 +520,10 @@ A: Open vSwitch has two kinds of flows (see the previous question), so
         dumps datapath flows for only the specified bridge, regardless
         of the type.
 
+Q: How does multicast snooping works with VLANs?
+
+A: Open vSwitch maintains snooping tables for each VLAN.
+
 
 Performance
 -----------
@@ -1103,6 +1128,12 @@ A: Do you have a controller configured on br0 (as the commands above
    OpenFlow controller doesn't see the VLANs that I expect," and you
    can refer to the answer there for more information.
 
+Q: How MAC learning works with VLANs?
+
+A: Open vSwitch implements Independent VLAN Learning (IVL) for
+   OFPP_NORMAL action.  I.e. it logically has separate learning tables
+   for each VLANs.
+
 
 VXLANs
 -----
@@ -1558,6 +1589,17 @@ A: These flows drop the ARP packets that IP hosts use to establish IP
       priority=5,in_port=1,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00,actions=2
       priority=5,in_port=2,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00,actions=1
 
+Q: My bridge disconnects from my controller on add-port/del-port.
+
+A: Reconfiguring your bridge can change your bridge's datapath-id because
+   Open vSwitch generates datapath-id from the MAC address of one of its ports.
+   In that case, Open vSwitch disconnects from controllers because there's
+   no graceful way to notify controllers about the change of datapath-id.
+
+   To avoid the behaviour, you can configure datapath-id manually.
+
+      ovs-vsctl set bridge br0 other-config:datapath-id=0123456789abcdef
+
 
 Development
 -----------