Clean up operational_considerations_hybrid.xml

Change-Id: I1584c11470e7525baa7159e560dc13957bdf5509
Implements: blueprint arch-guide

doc/arch-design/hybrid/section_operational_considerations_hybrid.xml

@@ -7,87 +7,69 @@
     <?dbhtml stop-chunking?>
     <title>Operational considerations</title>
     <para>Hybrid cloud deployments present complex operational
-        challenges. There are several factors to consider that affect
+        challenges. Differences between provider clouds can cause
-        the way each cloud is deployed and how users and operators
+        incompatibilities with workloads or Cloud Management
-        will interact with each cloud. Each cloud provider implements
+        Platforms (CMP). Cloud providers may also offer different levels of
-        infrastructure components differently. This can lead to incompatible
+        integration with competing cloud offerings.</para>
-        interactions with workloads, or a specific Cloud Management
+    <para>Monitoring is critical to maintaining a hybrid cloud, and it is
-        Platform (CMP). Different cloud providers may
+        important to determine if a CMP supports
-        also offer different levels of integration with competing
-        cloud offerings.</para>
-    <para>Monitoring is an important aspect to consider when selecting
-        a CMP. Gaining valuable insight into each
-        cloud is critical to gaining a holistic view of all involved
-        clouds. It is vital to determine whether an existing CMP supports
         monitoring of all the clouds involved, or if compatible APIs
-        are available to be queried for necessary information.
+        are available to be queried for necessary information.</para>
-        Gather all the information about each cloud, you can now take
-        appropriate actions on the offline data to avoid impacting workloads.</para>
 
     <section xml:id="agility">
       <title>Agility</title>
-    <para>The implemention of a hybrid cloud solution provides application
+    <para>Hybrid clouds provide application
         availability across different cloud environments and
         technologies. This availability enables the deployment to
         survive disaster in any single cloud environment.
-        Each cloud should provide the means to quickly spin up new
+        Each cloud should provide the means to create instances quickly
-        instances in the case of capacity issues or complete
+        in response to capacity issues or failure elsewhere in the hybrid
-        unavailability of a single cloud installation.</para>
+        cloud.</para>
     </section>
 
     <section xml:id="application-readiness-hybrid">
       <title>Application readiness</title>
-    <para>It is important to understand the type of application
+    <para>Enterprise workloads that depend on the
-        workload that is to be deployed across a hybrid cloud environment.
-        Enterprise workloads that depend on the
         underlying infrastructure for availability are not designed to
-        run on OpenStack. Although these types of applications can run
+        run on OpenStack. If the application cannot
-        on an OpenStack cloud, if the application is not able to
         tolerate infrastructure failures, it is likely to require
-        significant operator intervention to recover. However, cloud
+        significant operator intervention to recover. Applications for
-        workloads are designed to handle fault tolerance. The SLA
+        hybrid clouds must be fault tolerant, with an SLA that is not tied
-        of the application is not tied to the underlying
+        to the underlying infrastructure. Ideally, cloud applications should be
-        infrastructure. Ideally, cloud applications are designed
+        able to recover when entire racks and data centers experience an
-        to recover when entire racks and even data centers full of
+        outage.</para>
-        infrastructure experience an outage.</para>
     </section>
 
     <section xml:id="upgrades">
       <title>Upgrades</title>
-    <para>If the deployment includes a public cloud, predicting
+    <para>If a deployment includes a public cloud, predicting
-        upgrades may not be possible. Examine the advertised SLA for
+        upgrades may not be possible. Carefully examine provider SLAs.</para>
-        any public cloud provider being used.</para>
       <note>
         <para>At massive scale, even when
         dealing with a cloud that offers an SLA with a high percentage
-        of uptime, workloads must be able to recover at short
+        of uptime, workloads must be able to recover quickly.</para>
-        notice.</para>
       </note>
-    <para>When upgrading private cloud deployments, care
+    <para>When upgrading private cloud deployments, minimize disruption by
-        must be taken to minimize disruption by making incremental
+        making incremental changes and providing a facility to either rollback
-        changes and providing a facility to either rollback or
+        or continue to roll forward when using a continuous delivery
-        continue to roll forward when using a continuous delivery
         model.</para>
-    <para>Upgrades to the CMP may need to be completed in coordination
+    <para>You may need to coordinate CMP upgrades with hybrid cloud upgrades if
-        with any of the hybrid cloud upgrades. This is necessary
+        there are API changes.</para>
-        whenever API changes are made.</para>
     </section>
 
     <section xml:id="network-operation-center-noc">
       <title>Network Operation Center</title>
-    <para>It is important to recognize control over infrastructure particulates
+    <para>Consider infrastructure control
         when planning the Network Operation Center (NOC)
         for a hybrid cloud environment. If a significant
         portion of the cloud is on externally managed systems,
         prepare for situations where it may not be possible to
         make changes.
-        Additionally, situations of conflict may arise in which
+        Additionally, providers may differ on how
-        multiple providers have differing points of view on the way
         infrastructure must be managed and exposed. This can lead to
-        delays in root cause and analysis where each insists the blame
+        delays in root cause analysis where each insists the blame
         lies with the other provider.</para>
-    <para>It is important to ensure that the structure put in place
+    <para>Ensure that the network structure connects all clouds to form
-        enables connection of the networking of both clouds to form an
         integrated system, keeping in mind the state of handoffs.
         These handoffs must both be as reliable as possible and
         include as little latency as possible to ensure the best
@@ -96,15 +78,9 @@
 
     <section xml:id="maintainability">
       <title>Maintainability</title>
-    <para>Operating hybrid clouds is a situation in which there is a
+    <para>Hybrid clouds rely on third party systems and processes. As a
-        greater reliance on third party systems and processes. As a
+        result, it is not possible to guarantee
-        result of a lack of control of various pieces of a hybrid
+        proper maintenance of the overall system. Instead, be prepared to
-        cloud environment, it is not possible to guarantee
+        abandon workloads and recreate them in an improved state.</para>
-        proper maintenance of the overall system. Instead, the user
-        must be prepared to abandon workloads and spin them up again
-        in an improved state. Having a hybrid cloud deployment does,
-        however, provide agility for these situations by allowing the
-        migration of workloads to alternative clouds in response to
-        cloud-specific issues.</para>
      </section>
 </section>