Merge pull request #6864 from mburke5678/BZ-1518022

Add dnsmasq configuration per BZ

Author: mburke5678

install_config/upgrading/manual_upgrades.adoc

@@ -261,6 +261,93 @@ kubernetesMasterConfig:
 # systemctl enable origin-master-controllers
 ----
 
+. Configure Dnsmasq. Because of changes made in {product-title} 3.6, you will need to 
+perform the following steps to configure dnsmasq as part of the upgrade. See DNS Changes 
+under xref:../../release_notes/ocp_3_6_release_notes.adoc#ocp-36-notable-technical-changes[Notable Technical Changes]
+in the {product-title} 3.6 Release Notes.
++
+.. Create a *_/etc/origin/node/node-dnsmasq.conf_*  node configuration file.
++
+----  
+server=/in-addr.arpa/127.0.0.1
+server=/cluster.local/127.0.0.1
+----
+
+.. Edit the *_/etc/dnsmasq.d/origin-dns.conf_* file as follows:
++
+----  
+no-resolv
+domain-needed
+no-negcache
+max-cache-ttl=1
+enable-dbus
+bind-interfaces
+listen-address=<node_ip_address> <1>
+----
++
+<1> This is the IP address of the node host.
+
+.. Edit the *_/etc/dnsmasq.d/origin-upstream-dns.conf_* file as follows:
++
+---- 
+server=<dns_server1_ip_address>
+server=<dns_server2_ip_address>
+----
+
+.. Edit the *_/etc/origin/node/node-config.yaml_* as follows: 
++
+----
+dnsBindAddress: 127.0.0.1:53 
+dnsRecursiveResolvConf: /etc/origin/node/resolv.conf 
+dnsDomain: cluster.local 
+dnsIP: <node_ip_address> <1>
+----
++
+<1> This is the IP address of the node host.
+
+.. Update the *_/etc/systemd/system/atomic-openshift-node.service_* node systemd unit file: 
++
+----
+[Unit]
+Description=OpenShift Node
+After=docker.service
+Wants=openvswitch.service
+After=ovsdb-server.service
+After=ovs-vswitchd.service
+Wants=docker.service
+Documentation=https://github.com/openshift/origin
+Requires=dnsmasq.service
+After=dnsmasq.service
+
+[Service]
+Type=notify
+EnvironmentFile=/etc/sysconfig/atomic-openshift-node
+Environment=GOTRACEBACK=crash
+ExecStartPre=/usr/bin/cp /etc/origin/node/node-dnsmasq.conf /etc/dnsmasq.d/
+ExecStartPre=/usr/bin/dbus-send --system --dest=uk.org.thekelleys.dnsmasq /uk/org/thekelleys/dnsmasq uk.org.thekelleys.SetDomainServers array:string:/in-addr.arpa/127.0.0.1,/cluster.local/127.0.0.1
+ExecStopPost=/usr/bin/rm /etc/dnsmasq.d/node-dnsmasq.conf
+ExecStopPost=/usr/bin/dbus-send --system --dest=uk.org.thekelleys.dnsmasq /uk/org/thekelleys/dnsmasq uk.org.thekelleys.SetDomainServers array:string:
+ExecStart=/usr/bin/openshift start node --config=${CONFIG_FILE} $OPTIONS
+LimitNOFILE=65536
+LimitCORE=infinity
+WorkingDirectory=/var/lib/origin/
+SyslogIdentifier=atomic-openshift-node
+Restart=always
+RestartSec=5s
+TimeoutStartSec=300
+OOMScoreAdjust=-999
+
+[Install]
+WantedBy=multi-user.target
+----
++
+.. Reload systemd and restart node service. 
++
+----
+# systemctl daemon-reload 
+# systemctl restart atomic-openshift-node dnsmaq
+----
+
 . Restart the master service(s) on each master and review logs to ensure they
 restart successfully.
 +
@@ -311,6 +398,31 @@ IMAGE_VERSION=<tag>
 +
 Replace `<tag>` with `{latest-tag}` for the latest version.
 
+. Configure Dnsmasq. Because of changes made in {product-title} 3.6, you will need to 
+perform the following steps to configure dnsmasq as part of the upgrade. See DNS Changes 
+under xref:../../release_notes/ocp_3_6_release_notes.adoc#ocp-36-notable-technical-changes[Notable Technical Changes]
+in the {product-title} 3.6 Release Notes.
++
+.. Download the following script:
++
+----
+# wget https://raw.githubusercontent.com/openshift/openshift-ansible/release-3.6/roles/openshift_node_dnsmasq/files/networkmanager/99-origin-dns.sh -O /etc/NetworkManager/dispatcher.d/99-origin-dns.sh 
+# chmod 755 /etc/NetworkManager/dispatcher.d/99-origin-dns.sh 
+----
++
+This command downloads the *99-origin-dns.sh* script and copies the script to the *_/etc/NetworkManager/dispatcher.d/_* directory. 
+This script configure pods to use the node IP address as resolver. Using 127.0.0.1 inside a pod would fail.
+
+.. Edit the master DNS configuration file to listen on port 8053. This avoids conflicts on port 53 and opens port 8053 in the firewall.
+
+.. Restart Network Manager:
++
+----
+# systemctl restart NetworkManager
+----
+
+.. Edit the *_/etc/origin/node/node-config.yaml_* file to set the `dnsIP` field to the IP address of this node.
+
 . Restart the master service(s) on each master and review logs to ensure they
 restart successfully.
 +