fixed coding style

[sliver-openvswitch.git] / FAQ

diff --git a/FAQ b/FAQ
index 4a8a5be..2912ae3 100644 (file)
--- a/FAQ
+++ b/FAQ
@@ -418,7 +418,11 @@ A: First, why do you want to do this?  Two connected bridges are not
    ports will not work with the userspace datapath, only with the
    kernel module.
 
    ports will not work with the userspace datapath, only with the
    kernel module.
 

-Q: Why are there so many different ways to dump flows?
+
+Implementation Details
+----------------------
+
+Q: I hear OVS has a couple of kinds of flows.  Can you tell me about them?

 
 A: Open vSwitch uses different kinds of flows for different purposes:
 
 
 A: Open vSwitch uses different kinds of flows for different purposes:
 


@@ -434,18 +438,27 @@ A: Open vSwitch uses different kinds of flows for different purposes:
         about hidden flows.)
 
       - The Open vSwitch software switch implementation uses a second
         about hidden flows.)
 
       - The Open vSwitch software switch implementation uses a second

-        kind of flow internally.  These flows, called "exact-match"
-        or "datapath" or "kernel" flows, do not support wildcards or
-        priorities and comprise only a single table, which makes them
-        suitable for caching.   OpenFlow flows and exact-match flows
+        kind of flow internally.  These flows, called "datapath" or
+        "kernel" flows, do not support priorities and comprise only a
+        single table, which makes them suitable for caching.  (Like
+        OpenFlow flows, datapath flows do support wildcarding, in Open
+        vSwitch 1.11 and later.)  OpenFlow flows and datapath flows

         also support different actions and number ports differently.
 
         also support different actions and number ports differently.
 

-        Exact-match flows are an implementation detail that is
-        subject to change in future versions of Open vSwitch.  Even
-        with the current version of Open vSwitch, hardware switch
-        implementations do not necessarily use exact-match flows.
+        Datapath flows are an implementation detail that is subject to
+        change in future versions of Open vSwitch.  Even with the
+        current version of Open vSwitch, hardware switch
+        implementations do not necessarily use this architecture.
+
+   Users and controllers directly control only the OpenFlow flow
+   table.  Open vSwitch manages the datapath flow table itself, so
+   users should not normally be concerned with it.
+
+Q: Why are there so many different ways to dump flows?

 
 

-  Each of the commands for dumping flows has a different purpose:
+A: Open vSwitch has two kinds of flows (see the previous question), so
+   it has commands with different purposes for dumping each kind of
+   flow:

 
       - "ovs-ofctl dump-flows <br>" dumps OpenFlow flows, excluding
         hidden flows.  This is the most commonly useful form of flow
 
       - "ovs-ofctl dump-flows <br>" dumps OpenFlow flows, excluding
         hidden flows.  This is the most commonly useful form of flow


@@ -456,7 +469,7 @@ A: Open vSwitch uses different kinds of flows for different purposes:
         including hidden flows.  This is occasionally useful for
         troubleshooting suspected issues with in-band control.
 
         including hidden flows.  This is occasionally useful for
         troubleshooting suspected issues with in-band control.
 

-      - "ovs-dpctl dump-flows [dp]" dumps the exact-match flow table
+      - "ovs-dpctl dump-flows [dp]" dumps the datapath flow table

         entries for a Linux kernel-based datapath.  In Open vSwitch
         1.10 and later, ovs-vswitchd merges multiple switches into a
         single datapath, so it will show all the flows on all your
         entries for a Linux kernel-based datapath.  In Open vSwitch
         1.10 and later, ovs-vswitchd merges multiple switches into a
         single datapath, so it will show all the flows on all your


@@ -464,8 +477,8 @@ A: Open vSwitch uses different kinds of flows for different purposes:
         useful for debugging.
 
       - "ovs-appctl dpif/dump-flows <br>", new in Open vSwitch 1.10,
         useful for debugging.
 
       - "ovs-appctl dpif/dump-flows <br>", new in Open vSwitch 1.10,

-        dumps exact-match flows for only the specified bridge,
-        regardless of the type.
+        dumps datapath flows for only the specified bridge, regardless
+        of the type.

 
 
 Performance
 
 
 Performance