Weve initiated a new ISDN service to support our VOIP & data needs. The service is using 2 Cisco routers with one configured as VOIP router & the other as WAN. The ISP issued us 30 ip addresses for use on the data side but reserved 2 of the addresses to configure the routers. To enable VOIP services the engineers used the interface FastEthernet0/0 on both the WAN & VOIP routers and instructed us to use FastEthernet0/1 on the WAN router to connect for data. However when I try and assign an IP address to the FastEthernet0/1 connection I receive an IP address overlap error.
Is there a way to configure the FastEthernet0/1 connection using one of my remaining 28 ip addresses? Or should the ISP have given me a unique ip address separate from my block of data addresses to drive the VOIP interface? Ive been researching in Experts Exchange database for similar situations & possible solutions but have come up short.
Any assistance would be appreciated.