Hey All, I am attempting to configure a Cisco 1841 with (1) “WIC 1DSU-T1 V2” interface for use with WAN connectivity and (2) Fast Ethernet Interfaces for use with internal LAN connectivity. Bottom line is I am not a trained Cisco technician nor do I claim to possess any of the abilities of an experienced network tech. I am new to Cisco and don’t know everything about networking and would really appreciate it if I could get a few pointers as far as basic best practices when it comes to configuring this class of Cisco router. Obviously the config is minimal at best, right now my concerns are connectivity, I will address security concerns once I am confident the config is appropriate. Show Version & Show Run are as follows: router#sho ver Cisco IOS Software, 1841 Software (C1841-IPBASE-M), Version 12.4(1c), RELEASE SO FTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2005 by Cisco Systems, Inc. Compiled Tue 25-Oct-05 17:10 by evmiller ROM: System Bootstrap, Version 12.3(8r)T9, RELEASE SOFTWARE (fc1) router uptime is 0 minutes System returned to ROM by power-on System image file is "flash:c1841.bin" Cisco 1841 (revision 6.0) with 114688K/16384K bytes of memory. Processor board ID FTX1006W0AP 2 FastEthernet interfaces 1 Serial interface WIC T1-DSU DRAM configuration is 64 bits wide with parity disabled. 191K bytes of NVRAM. 31744K bytes of ATA CompactFlash (Read/Write) Configuration register is 0x2102 router# router# !------------------------! router# router# router#show run Building configuration... Current configuration : 953 bytes ! version 12.4 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname router ! boot-start-marker boot-end-marker ! enable secret 5 password ! no aaa new-model ! resource policy ! mmi polling-interval 60 no mmi auto-configure no mmi pvc mmi snmp-timeout 180 ip subnet-zero ip cef ! ! no ip dhcp use vrf connected ! ! no ip domain lookup ip name-server *.*.*.* ip name-server *.*.*.* ! ! ! ! interface FastEthernet0/0 description connected to EthernetLAN1 ip address 10.1.10.250 255.255.255.0 duplex auto speed auto ! interface FastEthernet0/1 description connected to EthernetLAN2 ip address 10.1.5.250 255.255.255.0 duplex auto speed auto ! interface Serial0/0/0 description connected to WAN ip address *.*.*.* 255.255.255.252 service-module t1 cablelength short 110ft ! router rip network 10.0.0.0 ! ip classless ! no ip http server ! ! control-plane ! ! line con 0 line aux 0 line vty 0 4 login ! end router# !------------------------! I have entered in the following configuration commands (found from a cisco doc relating specifically to my WIC card) however aside from the cable length command they do not appear in a show run...Are these all necessary to support a T1? Since they are not showing up in the config I am assuming they are not being properly applied to the routers configuration...? interface Serial0/0/0 ip address 10.0.0.51 255.0.0.0 service-module t1 framing esf service-module t1 linecode b8zs service-module t1 timeslots 1-12 speed 64 service-module t1 data-coding normal service-module t1 cablelength short 110ft service-module t1 remote-loopback full How is "cablelength" defined? From CSU/DSU, from D-Mark, etc? (I understand that the WIC card has a built-in CSU/DSU, will this disrupt anything if our location has a separate CSU/DSU provided by our ISP? !------------------------! What Routing protocol is best to utilize? This is all Greek to me, I found some configurations that utilized RIP (RIP V2?) but am open to whatever works best? !------------------------! Is this the proper way to designate a primary and secondary name server? Will it default to the top-most server? ip name-server *.*.*.* ip name-server *.*.*.* !------------------------! The Alarm Light is showing a solid amber state when the router is powered up. I currently do not have any cables going to the WIC and am assuming this is the source of the problem, When I connect an Ethernet cable (however the interface isn’t configured correctly yet either) the amber light stays on. Here is a show ip interface of the WIC: router#sho ip interface serial0/0/0 Serial0/0/0 is down, line protocol is down Internet address is *.*.*.*/* Broadcast address is *.*.*.* Address determined by non-volatile memory MTU is 1500 bytes Helper address is not set Directed broadcast forwarding is disabled Outgoing access list is not set Inbound access list is not set Proxy ARP is enabled Local Proxy ARP is disabled Security level is default Split horizon is enabled ICMP redirects are always sent ICMP unreachables are always sent ICMP mask replies are never sent IP fast switching is enabled IP fast switching on the same interface is enabled IP Flow switching is disabled IP CEF switching is enabled IP CEF Fast switching turbo vector IP multicast fast switching is enabled IP multicast distributed fast switching is disabled IP route-cache flags are Fast, CEF Router Discovery is disabled IP output packet accounting is disabled IP access violation accounting is disabled TCP/IP header compression is disabled RTP/IP header compression is disabled Policy routing is disabled Network address translation is disabled BGP Policy Mapping is disabled router# !------------------------! Thanks for all of the help it is much appreciated! My apologizes for the long post !------------------------!

cisco routers use encaplaction HDLC, by default - make sure on the other end router serial interface is using Cisco hdlc also, or you will never connect the two system's togther.