We had 5 major network maintenances planned in order to complete the core upgrade project and deploy MPLS VPNs. The first 2 are done: The first was disabling the IS-IS routing protocol (OSPF has been deployed along side IS-IS for some time). This was completed last Thursday. The second was replacing our primary border router (a Juniper M10) with a Cisco 6500. This was completed this morning and was the change that was giving me the most heartburn !
The next change is to swap out the secondary border router with a Cisco 6500 on Tuesday. We'll deploy BGP to all our core routers on Thursday. Currently only the border routers run BGP. BGP is needed on the core routers in order to support MPLS VPNs. The following Monday we will deploy MPLS and our first MPLS VPN.