ELCCR-1328 Remove mention about split-brain problem. It is

not clear at this point how the system behaves in this case.

Change-Id: I0cdb7b6d2cd59282a624a31a480e366a9830249d
Signed-off-by: Toma Bilius <toma.bilius@enea.com>

1 files changed, 33 insertions, 32 deletions

diff --git a/doc/book-enea-nfv-access-getting-started/doc/advanced_configurations.xml b/doc/book-enea-nfv-access-getting-started/doc/advanced_configurations.xml
index c85f30d..2a479b9 100644
--- a/doc/book-enea-nfv-access-getting-started/doc/advanced_configurations.xml
+++ b/doc/book-enea-nfv-access-getting-started/doc/advanced_configurations.xml
@@ -440,22 +440,21 @@ node0.1048576kB = 3 </programlisting>
     </figure>
 
     <para>The setup consists of two sub-clusters, placed in different
-    geographical locations. Each sub-cluster contains three MariaDB servers,
-    thus avoiding the split-brain problem. In this example, two of the
-    machines are running only MariaDB, while the rest are hosting a MariaDB
-    server and an Enea uCPE Manager instance. The entire network is hidden behind a
-    firewall that performs NAT. While in protection (cluster) mode, the
-    Enea uCPE Manager instances promote a Virtual IP (VIP) that represents the IP address of the
-    entire cluster. The firewall in this case will allocate a public IP for
-    the outside world that will be translated into the VIP. Also in this
-    example, the traffic towards the cluster from outside the firewall is done
-    through HTTPS, which will be translated to HTTP inside the private
-    network.</para>
+    geographical locations, each consisting of three MariaDB servers. In this
+    example, two of the machines are running only MariaDB, while the rest are
+    hosting a MariaDB server and an Enea uCPE Manager instance. The entire
+    network is hidden behind a firewall that performs NAT. While in protection
+    (cluster) mode, the Enea uCPE Manager instances promote a Virtual IP (VIP)
+    that represents the IP address of the entire cluster. The firewall in this
+    case will allocate a public IP for the outside world that will be
+    translated into the VIP. Also in this example, the traffic towards the
+    cluster from outside the firewall is done through HTTPS, which will be
+    translated to HTTP inside the private network.</para>
 
     <note>
-      <para>By default, communication to the Enea uCPE Manager is done with HTTPS.
-      To enable HTTP, go to <emphasis role="bold">System</emphasis>, <emphasis
-      role="bold">Configuration</emphasis>, click on the <emphasis
+      <para>By default, communication to the Enea uCPE Manager is done with
+      HTTPS. To enable HTTP, go to <emphasis role="bold">System</emphasis>,
+      <emphasis role="bold">Configuration</emphasis>, click on the <emphasis
       role="bold">Web Access</emphasis> tab and check the <emphasis
       role="bold">Enable HTTP</emphasis> checkbox.</para>
     </note>
@@ -510,11 +509,11 @@ node0.1048576kB = 3 </programlisting>
 
       <para>Please refer to <olink
       targetdoc="book_enea_nfv_access_getting_started"
-      targetptr="firewall_config">Firewall Configuration in the
-      <ns:include href="../../s_docbuild/olinkdb/pardoc-names.xml"
+      targetptr="firewall_config">Firewall Configuration in the <ns:include
+      href="../../s_docbuild/olinkdb/pardoc-names.xml"
       xmlns:ns="http://www.w3.org/2001/XInclude"
-      xpointer="element(book_enea_nfv_access_getting_started/1)" /></olink> Manual.
-      In addition, the following configuration is needed:</para>
+      xpointer="element(book_enea_nfv_access_getting_started/1)" /></olink>
+      Manual. In addition, the following configuration is needed:</para>
 
       <orderedlist>
         <listitem>
@@ -535,7 +534,7 @@ SELINUXTYPE=targeted</programlisting>
 
       <para>The following ports should be opened in the local firewall (not
       the one doing NAT), for each Enea uCPE Manager machine:</para>
-      
+
       <table>
         <title>Ports for Enea uCPE Manager Machines</title>
 
@@ -717,10 +716,10 @@ gpgcheck=1
 </programlisting></para>
 
             <note>
-              <para>For more information about setting the repository,
-              consult <ulink
-  url="https://downloads.mariadb.org/mariadb/repositories/#mirror=nxtHost">Downloads
-  - Setting up MariaDB Repositories</ulink>.</para>
+              <para>For more information about setting the repository, consult
+              <ulink
+              url="https://downloads.mariadb.org/mariadb/repositories/#mirror=nxtHost">Downloads
+              - Setting up MariaDB Repositories</ulink>.</para>
             </note>
           </listitem>
 
@@ -745,8 +744,8 @@ galera-4-26.4.6-1.el7.centos.x86_64</programlisting>
           </listitem>
 
           <listitem>
-            <para>Change the following configuration in 
-              <filename>/etc/my.cnf.d/wsrep.cnf</filename>:</para>
+            <para>Change the following configuration in
+            <filename>/etc/my.cnf.d/wsrep.cnf</filename>:</para>
 
             <programlisting># Full path to wsrep provider library or 'none'
 <emphasis role="bold">wsrep_provider=/usr/lib64/galera-4/libgalera_smm.so</emphasis>
@@ -877,11 +876,12 @@ TO 'enea'@'%' IDENTIFIED BY 'somepassword' WITH GRANT OPTION;</programlisting>
         PostgreSQL in the <ns:include
         href="../../s_docbuild/olinkdb/pardoc-names.xml"
         xmlns:ns="http://www.w3.org/2001/XInclude"
-        xpointer="element(book_enea_nfv_access_getting_started/1)" /></olink> 
-          Manual, for details on how to install and configure Java OpenJDK.</para>
-        
-        <para>Make sure the <literal>JAVA_HOME</literal> variable points to the 
-          OpenJDK 11 installation:</para>
+        xpointer="element(book_enea_nfv_access_getting_started/1)" /></olink>
+        Manual, for details on how to install and configure Java
+        OpenJDK.</para>
+
+        <para>Make sure the <literal>JAVA_HOME</literal> variable points to
+        the OpenJDK 11 installation:</para>
 
         <programlisting>[root@localhost ~]# echo $JAVA_HOME
 /usr/lib/jvm/java-11-openjdk-11.0.10.0.9-0.el7_9.x86_64
@@ -893,8 +893,9 @@ TO 'enea'@'%' IDENTIFIED BY 'somepassword' WITH GRANT OPTION;</programlisting>
         mode</title>
 
         <para>These steps must be taken on each of the CentOS 7 machines that
-        will host the Enea uCPE Manager. The Enea uCPE Manager will be installed 
-        and the setup for the external database cluster will be prepared.</para>
+        will host the Enea uCPE Manager. The Enea uCPE Manager will be
+        installed and the setup for the external database cluster will be
+        prepared.</para>
 
         <para>As the root user, go to the distribution folder of the Enea uCPE
         Manager, and run:</para>