Merge pull request #4281 from hashicorp/f-leave-on-terminate-docs

Doc updates to clarify leave_on_terminate

website/source/docs/agent/configuration/index.html.md

@@ -97,8 +97,8 @@ testing.
   the bind address of the specific network service if it is not provided. Any
   values configured in this stanza take precedence over the default
   [bind_addr](#bind_addr).
-    
-    If the bind address is `0.0.0.0` then the address 
+
+    If the bind address is `0.0.0.0` then the address
   private IP found is advertised. You may advertise an alternate port as well.
   The values support [go-sockaddr/template format][go-sockaddr/template].
 
@@ -155,11 +155,15 @@ testing.
 
 - `leave_on_interrupt` `(bool: false)` - Specifies if the agent should
   gracefully leave when receiving the interrupt signal. By default, the agent
-  will exit forcefully on any signal.
+  will exit forcefully on any signal. This value should only be set to true on
+  server agents if it is expected that a terminated server instance will never
+  join the cluster again.
 
 - `leave_on_terminate` `(bool: false)` - Specifies if the agent should
   gracefully leave when receiving the terminate signal. By default, the agent
-  will exit forcefully on any signal.
+  will exit forcefully on any signal. This value should only be set to true on
+  server agents if it is expected that a terminated server instance will never
+  join the cluster again.
 
 - `log_level` `(string: "INFO")` - Specifies  the verbosity of logs the Nomad
   agent will output. Valid log levels include `WARN`, `INFO`, or `DEBUG` in

website/source/intro/getting-started/running.html.md

@@ -110,7 +110,7 @@ Additional metadata can be viewed by providing the `-detailed` flag.
 
 You can use `Ctrl-C` (the interrupt signal) to halt the agent.
 By default, all signals will cause the agent to forcefully shutdown.
-The agent [can be configured](/docs/agent/configuration/index.html) to
+The agent [can be configured](/docs/agent/configuration/index.html#leave_on_terminate) to
 gracefully leave on either the interrupt or terminate signals.
 
 After interrupting the agent, you should see it leave the cluster
@@ -134,10 +134,13 @@ replication continues to be attempted until the node recovers. Nomad will
 automatically try to reconnect to _failed_ nodes, allowing it to recover from
 certain network conditions, while _left_ nodes are no longer contacted.
 
-If an agent is operating as a server, a graceful leave is important to avoid
-causing a potential availability outage affecting the
-[consensus protocol](/docs/internals/consensus.html). If a server does
-forcefully exit and will not be returning into service, the
+If an agent is operating as a server, [leave_on_terminate](/docs/agent/configuration/index.html#leave_on_terminate) should only
+be set if the server will never rejoin the cluster again. The default value of `false` for 'leave_on_terminate` and `leave_on_interrupt`
+work well for most scenarios. If Nomad servers are part of an auto scaling group where new servers are brought up to replace
+failed servers, using graceful leave avoids causing a potential availability outage affecting the [consensus protocol](/docs/internals/consensus.html).
+As of of Nomad 0.8, Nomad includes Autopilot which automatically removes failed or dead servers. This allows the operator to skip setting leave_on_terminate
+
+If a server does forcefully exit and will not be returning into service, the
 [`server force-leave` command](/docs/commands/server/force-leave.html) should
 be used to force the server from a _failed_ to a _left_ state.