[ovs-dev] [PATCH 2/2] FAQ: Add additional entries.
jpettit at nicira.com
Wed Jun 20 14:25:08 PDT 2012
This is great, Ben. I pushed it with your suggestions. Thanks.
On Jun 20, 2012, at 10:02 AM, Ben Pfaff wrote:
> On Tue, Jun 19, 2012 at 05:08:42PM -0700, Justin Pettit wrote:
>> +Q: What features are not available in the Open vSwitch kernel datapath
>> + that ships as part of the upstream Linux kernel?
>> +A: To avoid duplicating functionality in the kernel, certain features of
>> + Open vSwitch were left out of the upstream version. This includes
>> + bridge compatibility, which makes Open vSwitch work with the bridge
>> + utilities and exports many of its external interfaces.
>> + Additionally, dynamic tunneling support is not included. It is
>> + possible to create tunnels in Linux and attach them to Open vSwitch
>> + as system devices. However, they cannot be dynamically created
>> + through the OVSDB protocol or set the tunnel ids as a flow action.
> Hmm. I think we could be more specific:
> A: The kernel module in upstream Linux 3.3 and later does not include
> the following features:
> - Bridge compatibility, that is, support for the ovs-brcompatd
> daemon that (if you enable it) lets "brctl" and other Linux
> bridge tools transparently work with Open vSwitch instead.
> We do not expect bridge compatibility to ever be available in
> upstream Linux. If you need bridge compatibility, use the
> kernel module from the Open vSwitch distribution instead of the
> upstream Linux kernel module.
> - Tunnel and patch virtual ports, that is, interfaces with type
> "gre", "ipsec_gre", "capwap", or "patch". It is possible to
> create tunnels in Linux and attach them to Open vSwitch as
> system devices. However, they cannot be dynamically created
> through the OVSDB protocol or set the tunnel ids as a flow
> Work is in progress in adding these features to the upstream
> Linux version of the Open vSwitch kernel module. For now, if
> you need these features, use the kernel module from the Open
> vSwitch distribution instead of the upstream Linux kernel
>> +Q: What features are not available when using the userspace datapath?
>> +A: Similar to the upstream kernel datapath, dynamic tunneling is not
>> + supported. It is also not possible to use queue-related actions.
>> + On older Linux kernels, maximum-sized VLAN packets may not be
>> + transmitted.
> How about:
> A: Tunnel and patch virtual ports are not supported, as described in the
> previous answer. It is also not possible to use queue-related
> actions. On Linux kernels before 2.6.39, maximum-sized VLAN packets
> may not be transmitted.
More information about the dev