Merge pull request docker#678 from joaofnfernandes/dtr-health-checks

Add more information about DTR healthchecks

datacenter/dtr/2.1/guides/high-availability/index.md

@@ -74,7 +74,7 @@ Make sure you configure your load balancer to:
 
 * Load-balance TCP traffic on ports 80 and 443,
 * Not terminate HTTPS connections,
-* Use the `/load_balancer_status` endpoint on each DTR replica, to check if
+* Use the `/health` endpoint on each DTR replica, to check if
 the replica is healthy and if it should remain on the load balancing pool or
 not.
 

datacenter/dtr/2.1/guides/monitor-troubleshoot/index.md

@@ -25,6 +25,21 @@ resources, and logs.
 
 ![](../images/monitor-2.png)
 
+## Health checks
+
+DTR also exposes several endpoints you can use to assess if a DTR replica
+is healthy or not:
+
+* `/health`: Checks if the several components of a DTR replica are healthy, and
+returns a simple json response. This is useful for load balancing or other
+automated health check tasks.
+* `/load_balancer_status`: Checks if the several components of a DTR replica
+can be reached, and displays that information in a table. This is useful for
+an administrator to gauge the status of a DTR replica.
+* `/nginx_status`: Returns the number of connections being handled by the
+NGINX front-end used by DTR.
+* `/api/v0/meta/cluster_status`: Returns extensive information about all DTR
+replicas.
 
 ## Where to go next