ISND / DDR Call Status confusion

Hi all,

I'm working on a lab in the Boson sim that deals with ISDN and legacy DDR. The lab has me set up an ISDN switched connection between two routers. I did, the pings work and things seem to be happy enough.

In looking at status, both bri0 interfaces are up/up, but both B channels for each of these interfaces are down/down since there is no active call. The lab then has you initiate a ping from one of the routers to the other using it's isdn interface address.

They then want you to check the status of the B channels and see that one of them is up with the reasoning that the ping has "established" a call. When I check isdn status, both B channels still show down/down.

I'm thinking this is probably what I should see since I wouldn't expect the connection to remain beyond what is necessary to satisfy the ping, but then I'm just guessing. Anyone care to weigh in on what you think should happen?

router1(config)# isdn switch-type basic-ni
router1(config)# dialer-list 1 protocol ip permit
router1(config)# username router2 password cisco
router1(config)# interface bri0
router1(config-if)# encapsulate ppp
router1(config-if)# ip address 200.10.1.1 255.255.255.0
router1(config-if)# isdn spid1 32177820010100
router1(config-if)# dialer-group 1
router1(config-if)# dialer map ip 200.10.1.2 name router2 broadcast 7782001
router1(config-if)# ppp authentication chap
router1(config-if)# no shut

router2(config)# isdn switch-type basic-ni
router2(config)# dialer-list 1 protocol ip permit
router2(config)# username router1 password cisco
router2(config)# interface bri0
router2(config-if)# encapsulate ppp
router2(config-if)# ip address 200.10.1.2 255.255.255.0
router2(config-if)# isdn spid1 32177820020100
router2(config-if)# dialer-group 1
router2(config-if)# dialer map ip 200.10.1.1 name router1 broadcast 7782002
router2(config-if)# ppp authentication chap
router2(config-if)# no shut

router1# ping 200.10.1.2 [here the ping succeeds]
router1# show isdn status [still shows no active calls]
router1# show interfaces bri0 1 2 [both channels still down/down]:

Many thanks

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Comments

captobvious

First I'd check this (you'll need a login):

640-802 CCNA® Exam Topics (Blueprint)

to see if you find ISDN anywhere. Then I'd move on to the next lab.

KPWright

Had the login, thanks for the link and the practical advice. Doesn't mention ISDN directly, I'd assume the content would fit under the WAN / PPP configuration topics if at all. The lab is defined in something titled "NETSIM FOR CCNA LAB MANUAL", but I'm tempted to **** it anyway (I'm thinkin' it's "broke").

In the interim I cleaned house and re-loaded the starting lab configuration. This time after running through the configuration steps and showing isdn status for each router, both show the layer 1 status to be "Testing" instead of "Active" as they showed the first time. I found a brief reference in a Cisco doc to this as an "other" status that may show up in the output and indicated a "clear...." should remove it. It didn't.

I'm moving on. Thanks for grounding me

captobvious

No worries. Good luck on your studies!