Merge pull request #4586 from pacevedom/USHIFT-5402

USHIFT-5402: Handle DUID in ipv6 test harness

Author: openshift-merge-bot[bot]

test/kickstart-templates/includes/post-network.cfg

@@ -17,3 +17,24 @@ find /etc/NetworkManager -name '*.nmconnection' -print0 | while IFS= read -r -d
         sed -i 's/method=.*/method=auto/g' "${file}"
     fi
 done
+
+# IPv6 only feature. An IPv6 VM will use DHCPv6 to get an IP address. To identify itself to a DHCP
+# server it uses something called DHCP Unique Identifier (DUID), and based on that the DHCP server
+# will issue a lease for that DUID and MAC address. When the system boots into anaconda to install
+# the OS with kickstart files, the DUID is automatically generated. After the system boots into the
+# OS a new DUID may be generated, causing DHCP to identify the VM as a new system, thus allocating
+# a new IP address. In order to avoid this, the DUID generated during the installation is saved and
+# configured in NetworkManager to use it when the system boots into the OS.
+# The DUID is unique per host, and is extracted from the DHCP6 options of the active connections
+# from NetworkManager.
+DUID=$(nmcli con show --active | \
+  awk '{print $1}' | \
+  grep -v NAME | \
+  xargs nmcli --fields DHCP6.OPTION con show | \
+  grep dhcp6_client_id | \
+  awk '{print $4}' | \
+  uniq)
+if [ -n "$DUID" ]; then
+    mkdir -p /etc/NetworkManager/conf.d/
+    echo -e "[connection]\nipv6.dhcp-duid=$DUID" > /etc/NetworkManager/conf.d/dhcp-client.conf
+fi