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Draft 1721 router config (frame relay to WIC T1 DSU/CSU to ENET Lan I/F)

Need another pair of eyes to review the following draft config. The objective is to connect an internal Lan to the Internet via Frame Relay circuit using a Cisco 1721 router with WIC T1 DSU/CSU and Ethernet Lan Interface. Firewall connection intentionally left out for simplicity.

Helpful criticism wille gratefully accepted.


version 12.3

service timestamps debug datetime localtime show-timezone

service timestamps log datetime localtime show-timezone

no service password-encryption


hostname xxxxxxxxxxxx





enable secret xxxx.

enable password xxxxx


clock timezone EST -5

clock summer-time EDT recurring

mmi polling-interv

no mmi auto-configure

no mmi pvc

mmi snmp-timeout 180

no aaa new-model

ip subnet-zero

ip cef




no ftp-server write-enable





interface FastEthernet0

description To office Ethernet

ip address

speed auto

no keepalive


interface Serial0

description To UUNET (xxxxxxxxxxxx)

bandwidth 1536

no ip address

encapsulation frame-relay IETF

no fair-queue

frame-relay interface-dlci xxx

frame-relay lmi-type ansi


ip classless

ip route Serial0

no ip http server


access-list 3 remark Default reference clock for local use

access-list 3 remark Massachusetts Institute of Technology Timeclock

access-list 3 permit

access-list 3 remark ViaNet Communications Timeclock

access-list 3 permit xxx.xx.x.x

access-list 3 deny any log


line con 0

line aux 0

line vty 0 4

password cisco



ntp clock-period 17180092

ntp source FastEthernet0

ntp access-group peer 3

ntp server source FastEthernet0 prefer

ntp server xxx.xx.x.x source FastEthernet0




Re: Draft 1721 router config (frame relay to WIC T1 DSU/CSU to E


Here's a couple of things:

- what size is your Internet PVC ? you have not enabled any traffic shaping. Unless your PVC is the same size as the access rate, it may be advisable to turn on shaping.

- why have you hard-coded the LMI type to ANSI ? Is this what the ISP uses ? If not, you could just remove that command and the router will auto-detect it....

- your default route points to a multiaccess segment...This is not a good idea .. Instead of doing that, configure it with an IP next-hop..

Hope that helps - pls rate the post if it does.



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