Set extension for custom DNS (#3264)

Azure · Jun 15, 2018 · e0cb223 · e0cb223
1 parent 9455a82
commit e0cb223
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Showing 2 changed files with 69 additions and 8 deletions.
diff --git a/examples/vnet/kubernetesvnet-customnodesdns.json b/examples/vnet/kubernetesvnet-customnodesdns.json
@@ -10,24 +10,37 @@
       "masterProfile": {
         "count": 1,
         "dnsPrefix": "test",
-        "vmSize": "Standard_D2_v2",
+        "vmSize": "Standard_D2_v3",
         "vnetSubnetId": "/subscriptions/SUB_ID/resourceGroups/RG_NAME/providers/Microsoft.Network/virtualNetworks/VNET_NAME/subnets/SUBNET_NAME",
-        "firstConsecutiveStaticIP": "10.239.255.239" 
+        "firstConsecutiveStaticIP": "10.239.255.239",
+        "vnetCidr": "10.22.221.0/24",
+        "preProvisionExtension": {
+          "name": "register-dns",
+          "singleOrAll": "All"
+        }
       },
       "agentPoolProfiles": [
         {
-          "name": "agentpri",
+          "name": "staging",
           "count": 2,
-          "vmSize": "Standard_D2_v2",
+          "vmSize": "Standard_D2_v3",
           "vnetSubnetId": "/subscriptions/SUB_ID/resourceGroups/RG_NAME/providers/Microsoft.Network/virtualNetworks/VNET_NAME/subnets/SUBNET_NAME",
-          "availabilityProfile": "AvailabilitySet"
+          "availabilityProfile": "VirtualMachineScaleSets",
+          "preProvisionExtension": {
+            "name": "register-dns",
+            "singleOrAll": "All"
+          }
         },
         {
-          "name": "agentpri2",
+          "name": "production",
           "count": 2,
-          "vmSize": "Standard_D2_v2",
+          "vmSize": "Standard_D2_v3",
           "vnetSubnetId": "/subscriptions/SUB_ID/resourceGroups/RG_NAME/providers/Microsoft.Network/virtualNetworks/VNET_NAME/subnets/SUBNET_NAME",
-          "availabilityProfile": "AvailabilitySet"
+          "availabilityProfile": "VirtualMachineScaleSets",
+          "preProvisionExtension": {
+            "name": "register-dns",
+            "singleOrAll": "All"
+          }
         }
       ],
       "linuxProfile": {
@@ -43,6 +56,15 @@
           ]
         }
       },
+      "extensionProfiles": [
+        {
+          "name": "register-dns",
+          "version": "v1",
+          "extensionParameters": "mydomain.com",
+          "rootURL": "https://raw.githubusercontent.com/Azure/acs-engine/master/extensions/dnsupdate/",
+          "script": "register-dns.sh"
+        }
+      ],
       "servicePrincipalProfile": {
         "clientId": "",
         "secret": ""

diff --git a/extensions/dnsupdate/v1/register-dns.sh b/extensions/dnsupdate/v1/register-dns.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+# Add support for registering host on dns server. Must allow non-secure updates
+
+set -e
+
+DOMAINNAME=$1
+
+echo $(date) " - Starting Script"
+
+cat > /etc/network/if-up.d/register-dns <<EOFDHCP
+#!/bin/sh
+
+# only execute on the primary nic
+if [ "\${IFACE}" = "eth0" ]
+then
+    ip=\$(ip address show eth0 | awk '/inet / {print \$2}' | cut -d/ -f1)
+    host=\$(hostname -s)
+    nsupdatecmds=/var/tmp/nsupdatecmds
+    echo "update delete \${host}.${DOMAINNAME} a" > \$nsupdatecmds
+    echo "update add \${host}.${DOMAINNAME} 3600 a \${ip}" >> \$nsupdatecmds
+    echo "send" >> \$nsupdatecmds
+
+    nsupdate \$nsupdatecmds
+fi
+EOFDHCP
+
+chmod 755 /etc/network/if-up.d/register-dns
+
+if ! grep -Fq "${DOMAINNAME}" /etc/dhcp/dhclient.conf
+then
+    echo $(date) " - Adding domain to dhclient.conf"
+
+    echo "supersede domain-name \"${DOMAINNAME}\";" >> /etc/dhcp/dhclient.conf
+    echo "prepend domain-search \"${DOMAINNAME}\";" >> /etc/dhcp/dhclient.conf
+fi
+
+# service networking restart
+echo $(date) " - Restarting network"
+sudo ifdown eth0 && sudo ifup eth0