Fun With Basic ATM And OSPF On Cisco
While not as exciting as my EIGRP over GRE over PPP over T1 article, today we’ll setup a DS3 connection between a Cisco 7204VXR and Cisco 2621XM with a little OSPF mixed in. The 7204VXR has the PA-A3-T3 “ATM WAN DS3 Port Adaptor” and the 2621XM has the NM-ATM-DS3 “ATM DS3” module.
First we’ll bring up the ATM interface on the 7204VXR. The only thing we’re adding to ATM3/0 is enabling scrambling because it sounds cool. Our actual IP config is done by creating ATM3/0.1 as point-to-point.
interface ATM3/0 no ip address no ip route-cache atm scrambling cell-payload no atm ilmi-keepalive no atm enable-ilmi-trap interface ATM3/0.1 point-to-point ip address 10.60.254.1 255.255.255.252 no ip route-cache no atm enable-ilmi-trap cdp enable pvc 0/40 oam-pvc manage encapsulation aal5snap
Now we’ll bring up the 2621XM side.
interface ATM1/0 no ip address atm scrambling cell-payload no atm ilmi-keepalive interface ATM1/0.1 point-to-point ip address 10.60.254.2 255.255.255.252 cdp enable pvc 0/40 oam-pvc manage encapsulation aal5snap
Did it work?
c7204vxr#sh cdp nei atm3/0.1 Device ID Local Intrfce Holdtme Capability Platform Port ID c2621xm ATM3/0.1 158 R S I 2621XM ATM1/0.1
OK. Time for some OSPF or whatever. On the 7204VXR I’ve put 10.44.44.1/24 in Lo1 for area 5, and on the 2621XM I’ve put 10.44.45.1/24 in Lo1 for area 10.
7204VXR:
router ospf 1 router-id 10.60.254.1 passive-interface default no passive-interface ATM3/0.1 network 10.44.44.0 0.0.0.255 area 5 network 10.60.254.0 0.0.0.3 area 0
2621XM:
router ospf 1 router-id 10.60.254.2 passive-interface default no passive-interface ATM1/0.1 network 10.44.45.0 0.0.0.255 area 10 network 10.60.254.0 0.0.0.3 area 0
Did it work?
c7204vxr#sh ip ospf nei Neighbor ID Pri State Dead Time Address Interface 10.60.254.2 0 FULL/ - 00:00:36 10.60.254.2 ATM3/0.1 c7204vxr#sh ip route ospf O IA 10.44.45.1/32 [110/3] via 10.60.254.2, 00:44:54, ATM3/0.1
I guess so.
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