Reduce heading levels by 1.

docs/tutorials/stateful-application/zookeeper.md

@@ -58,7 +58,7 @@ After this tutorial, you will know the following.
 
 {% capture lessoncontent %}
 
-#### ZooKeeper Basics
+### ZooKeeper Basics
 
 [Apache ZooKeeper](https://zookeeper.apache.org/doc/current/) is a 
 distributed, open-source coordination service for distributed applications.
@@ -86,7 +86,7 @@ snapshot their in memory state to storage media. These snapshots can be loaded
 directly into memory, and all WAL entries that preceded the snapshot may be 
 safely discarded.
 
-### Creating a ZooKeeper Ensemble
+## Creating a ZooKeeper Ensemble
 
 The manifest below contains a 
 [Headless Service](/docs/user-guide/services/#headless-services), 
@@ -145,7 +145,7 @@ zk-2      1/1       Running   0         40s
 The StatefulSet controller creates three Pods, and each Pod has a container with 
 a [ZooKeeper 3.4.9](http://www-us.apache.org/dist/zookeeper/zookeeper-3.4.9/) server.
 
-#### Facilitating Leader Election
+### Facilitating Leader Election
 
 As there is no terminating algorithm for electing a leader in an anonymous 
 network, Zab requires explicit membership configuration in order to perform 
@@ -242,7 +242,7 @@ server.2=zk-1.zk-headless.default.svc.cluster.local:2888:3888
 server.3=zk-2.zk-headless.default.svc.cluster.local:2888:3888
 ```
 
-#### Achieving Consensus
+### Achieving Consensus
 
 Consensus protocols require that the identifiers of each participant be 
 unique. No two participants in the Zab protocol should claim the same unique 
@@ -301,7 +301,7 @@ and at least two of the Pods are Running and Ready), or they will fail to do so
 (if either of the aforementioned conditions are not met). No state will arise 
 where one server acknowledges a write on behalf of another.
 
-#### Sanity Testing the Ensemble
+### Sanity Testing the Ensemble
 
 The most basic sanity test is to write some data to one ZooKeeper server and 
 to read the data from another. 
@@ -348,7 +348,7 @@ dataLength = 5
 numChildren = 0
 ```
 
-#### Providing Durable Storage
+### Providing Durable Storage
 
 As mentioned in the [ZooKeeper Basics](#zookeeper-basics) section,
 ZooKeeper commits all entries to a durable WAL, and periodically writes snapshots 
@@ -507,7 +507,7 @@ same PersistentVolume mounted to the ZooKeeper server's data directory.
 Even when the Pods are rescheduled, all of the writes made to the ZooKeeper 
 servers' WALs, and all of their snapshots, remain durable.
 
-### Ensuring Consistent Configuration
+## Ensuring Consistent Configuration
 
 As noted in the [Facilitating Leader Election](#facilitating-leader-election) and
 [Achieving Consensus](#achieving-consensus) sections, the servers in a 
@@ -651,7 +651,7 @@ ZK_DATA_LOG_DIR=/var/lib/zookeeper/log
 ZK_LOG_DIR=/var/log/zookeeper
 ```
 
-#### Configuring Logging
+### Configuring Logging
 
 One of the files generated by the `zkConfigGen.sh` script controls ZooKeeper's logging. 
 ZooKeeper uses [Log4j](http://logging.apache.org/log4j/2.x/), and, by default, 
@@ -721,7 +721,7 @@ For cluster level log shipping and aggregation, you should consider deploying a
 [sidecar](http://blog.kubernetes.io/2015/06/the-distributed-system-toolkit-patterns.html) 
 container to rotate and ship your logs.
 
-#### Configuring a Non-Privileged User
+### Configuring a Non-Privileged User
 
 The best practices with respect to allowing an application to run as a privileged 
 user inside of a container are a matter of debate. If your organization requires 
@@ -773,7 +773,7 @@ and the ZooKeeper process is able to successfully read and write its data.
 drwxr-sr-x 3 zookeeper zookeeper 4096 Dec  5 20:45 /var/lib/zookeeper/data
 ```
 
-### Managing the ZooKeeper Process
+## Managing the ZooKeeper Process
 
 The [ZooKeeper documentation](https://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_supervision) 
 documentation indicates that "You will want to have a supervisory process that 
@@ -783,7 +783,7 @@ common pattern. When deploying an application in Kubernetes, rather than using
 an external utility as a supervisory process, you should use Kubernetes as the 
 watchdog for your application.
 
-#### Handling Process Failure 
+### Handling Process Failure 
 
 
 [Restart Policies](/docs/user-guide/pod-states/#restartpolicy) control how 
@@ -846,7 +846,7 @@ child process. This ensures that Kubernetes will restart the application's
 container when the process implementing the application's business logic fails. 
 
 
-#### Testing for Liveness
+### Testing for Liveness
 
 
 Configuring your application to restart failed processes is not sufficient to 
@@ -918,7 +918,7 @@ zk-0      1/1       Running   1         1h
 ```
 
 
-#### Testing for Readiness
+### Testing for Readiness
 
 
 Readiness is not the same as liveness. If a process is alive, it is scheduled 
@@ -951,7 +951,7 @@ to specify both. This ensures that only healthy servers in the ZooKeeper
 ensemble receive network traffic.
 
 
-### Tolerating Node Failure
+## Tolerating Node Failure
 
 ZooKeeper needs a quorum of servers in order to successfully commit mutations 
 to data. For a three server ensemble, two servers must be healthy in order for 
@@ -1013,7 +1013,7 @@ Service in the domain defined by the `topologyKey`. The `topologyKey`
 different rules, labels, and selectors, you can extend this technique to spread 
 your ensemble across physical, network, and power failure domains.
 
-### Surviving Maintenance
+## Surviving Maintenance
 
 **In this section you will cordon and drain nodes. If you are using this tutorial
 on a shared cluster, be sure that this will not adversely affect other tenants.**