[VOL-3373] Updating voltha docs with califications and more links

Change-Id: If37468e130446164737467bec32c7fd28ed32320
diff --git a/overview/lab_setup.rst b/overview/lab_setup.rst
index 5ec8054..2659b0d 100644
--- a/overview/lab_setup.rst
+++ b/overview/lab_setup.rst
@@ -143,10 +143,10 @@
 
 To setup a NAT router on an Ubuntu 16.04 server you can look at this
 tutorial:
-https://www.nairabytes.net/81-linux/418-how-to-set-up-a-nat-router-on-ubuntu-server-16-04
+http://nairabytes.net/linux/how-to-set-up-a-nat-router-on-ubuntu-server-16-04
 
 To install a DHCP server you can follow this tutorial:
-http://nairabytes.net/81-linux/415-how-to-install-a-dhcp-server-in-ubuntu-server-16-04
+http://nairabytes.net/linux/how-to-install-a-dhcp-server-in-ubuntu-server-16-04
 
 Once the ``DHCP`` server is installed, you need to configure it.