diff mbox series

[ovs-dev,3/8] ovn-nb: Improve documentation of health checks.

Message ID 20201022035415.33541-3-blp@ovn.org
State Accepted
Headers show
Series [ovs-dev,1/8] ovn-nb: Better document dynamic addresses. | expand

Commit Message

Ben Pfaff Oct. 22, 2020, 3:54 a.m. UTC
Signed-off-by: Ben Pfaff <blp@ovn.org>
---
 ovn-nb.xml | 59 +++++++++++++++++++++++++++++++-----------------------
 1 file changed, 34 insertions(+), 25 deletions(-)
diff mbox series

Patch

diff --git a/ovn-nb.xml b/ovn-nb.xml
index 5a8ac4a0d0e0..27d6d056e508 100644
--- a/ovn-nb.xml
+++ b/ovn-nb.xml
@@ -1510,36 +1510,45 @@ 
       </p>
     </column>
 
-    <column name="health_check">
-      Load balancer health checks associated with this load balancer.
-      If health check is desired for a vip's endpoints defined in
-      the <ref column="vips" table="Load_Balancer" db="OVN_Northbound"/>
-      column, then a row in the table
-      <ref table="Load_Balancer_Health_Check" db="OVN_Northbound"/> should
-      be created and referenced here and L4 port should be defined
-      for the vip and it's endpoints. Health checks are supported only
-      for IPv4 load balancers.
-    </column>
-
-    <column name="ip_port_mappings">
+    <group title="Health Checks">
       <p>
-        This column is used if load balancer health checks are enabled.
-        This keeps a mapping of endpoint IP to the logical port name.
-        The source ip to be used for health checks is also expected to be
-        defined. The key of the mapping is the endpoint IP and the value
-        is in the format : <code>port_name:SRC_IP</code>
+        OVN supports health checks for load balancer endpoints, for IPv4 load
+        balancers only.  When health checks are enabled, the load balancer uses
+        only healthy endpoints.
       </p>
 
       <p>
-        Eg. If there is a VIP entry:
-        <code>"10.0.0.10:80=10.0.0.4:8080,20.0.0.4:8080"</code>,
-        then the IP to port mappings should be defined as:
-        <code>"10.0.0.4"="sw0-p1:10.0.0.2"</code> and
-        <code>"20.0.0.4"="sw1-p1:20.0.0.2"</code>. <code>10.0.0.2</code>
-        and <code>20.0.0.2</code> will be used by <code>ovn-controller</code>
-        as source ip when it sends out health check packets.
+        Suppose that <ref column="vips"/> contains a key-value pair
+        <code>10.0.0.10:80</code>=<code>10.0.0.4:8080,20.0.0.4:8080</code>.  To
+        enable health checks for this virtual's endpoints, add two key-value
+        pairs to <ref column="ip_port_mappings"/>, with keys
+        <code>10.0.0.4</code> and <code>20.0.0.4</code>, and add to <ref
+        column="health_check"/> a reference to a <ref
+        table="Load_Balancer_Health_Check"/> row whose <ref
+        table="Load_Balancer_Health_Check" column="vip"/> is set to
+        <code>10.0.0.10</code>.
       </p>
-    </column>
+
+      <column name="health_check">
+        Load balancer health checks associated with this load balancer.
+      </column>
+
+      <column name="ip_port_mappings">
+        <p>
+          Maps from endpoint IP to a colon-separated pair of logical port name
+          and source IP,
+          e.g. <code><var>port_name</var>:<var>sourc_ip</var></code>.  Health
+          checks are sent to this port with the specified source IP.
+        </p>
+
+        <p>
+          For example, in the example above, IP to port mappings might be
+          defined as <code>10.0.0.4</code>=<code>sw0-p1:10.0.0.2</code> and
+          <code>20.0.0.4</code>=<code>sw1-p1:20.0.0.2</code>, if the values
+          given were suitable ports and IP addresses.
+        </p>
+      </column>
+    </group>
 
     <column name="selection_fields">
       <p>