doc: Fix non-existing URLs

Change-Id: I72c1c0fcb7cc541b87b184b32f0797539b919a44
Closes-Bug: #1708394

doc/source/contributor/index.rst

@@ -27,6 +27,10 @@
 Contributor Guide
 =================
 
+This document describes Neutron for contributors of the project, and assumes
+that you are already familiar with Neutron from an
+:doc:`end-user perspective </admin/index>`.
+
 Neutron Policies
 ----------------
 

doc/source/contributor/internals/layer3.rst

@@ -250,7 +250,8 @@ Neutron can also be configured to create `provider networks <http://docs.opensta
 
 Further Reading
 ---------------
+
 * `Packet Pushers - Neutron Network Implementation on Linux <http://packetpushers.net/openstack-quantum-network-implementation-in-linux/>`_
 * `OpenStack Administrator Guide <http://docs.openstack.org/admin-guide/networking.html>`_
-* `Neutron - Layer 3 API extension usage guide <http://docs.openstack.org/api/openstack-network/2.0/content/router_ext.html>`_
-*  `Darragh O'Reilly -  The Quantum L3 router and floating IPs <http://techbackground.blogspot.com/2013/05/the-quantum-l3-router-and-floating-ips.html>`_
+* `Neutron - Layer 3 API extension <https://developer.openstack.org/api-ref/networking/v2/index.html#layer-3-networking>`_
+* `Darragh O'Reilly -  The Quantum L3 router and floating IPs <http://techbackground.blogspot.com/2013/05/the-quantum-l3-router-and-floating-ips.html>`_

doc/source/index.rst

@@ -21,12 +21,7 @@ Neutron is an OpenStack project to provide "network connectivity as a service"
 between interface devices (e.g., vNICs) managed by other OpenStack services
 (e.g., nova). It implements the `Neutron API`_.
 
-.. _`Neutron API`: http://docs.openstack.org/api/openstack-network/2.0/content/
-
-This document describes Neutron for contributors of the project, and assumes
-that you are already familiar with Neutron from an `end-user perspective`_.
-
-.. _`end-user perspective`: http://docs.openstack.org/trunk/openstack-network/admin/content/index.html
+.. _`Neutron API`: https://developer.openstack.org/api-ref/networking/
 
 This documentation is generated by the Sphinx toolkit and lives in the source
 tree.  Additional documentation on Neutron and other components of OpenStack