Lab: Can't get T1's to work at all...

I've got a 3620 with (4) 1DSU-T1 cards. I also have a 1841 and a 2801 with a total of (3) 1DSU-T1 v2 cards.

I can't seem to get anything to work on them. I was following Chris Bryants CCENT video tutorial and just got to the frame relay point. I planned on using the T1 cards instead of serials for my lab.

Using several crossover cables, I was able to get the links up and even the protocols up, but I could never ping an ip address - not even the local ip assigned to the T1 card.

I then opted to just try and setup a point to point connection to see if I had any physical layer problems. To be honest, I don't think I have any physical problems - and I've made three crossover cables now as well - and I believe it's me in my configurations.

1. Is the 1DSU-T1 compatible with the 1DSU-T1 v2 cards?

2. I'm using 3 foot crossover cables and noticed a short cable command. Do I need to use this?

I'm just trying to assign an IP to the serial0/1/0 just like I do with an ethernet port but I'm not able to ping it.

!
interface Serial0/0/0
ip address 172.12.123.2 255.255.255.0
encapsulation frame-relay
no ip route-cache
logging event subif-link-status
logging event dlci-status-change
fair-queue
no frame-relay inverse-arp
!

Any suggestions/comments would be GREATLY APPRECIATED!

Have a wonderful day!
Your friend in Virginia,
Paul L.

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Comments

mikej412

ptlinva wrote: »

no frame-relay inverse-arp

If you're going to disable inverse-arp, then you have to do manual layer 2 to layer 3 address mapping. That also includes a map to ping your local address.

It's probably easier to configure a full mesh and use inverse arp to test your frame switch configuration. Then get fancy

georgemc

What pinout were you using for you crossover cable? If you're not alread doing so, us a cable that crosses 1,2, 4, and 5.

1 <--> 4
2 <--> 5
4 <--> 1
5 <--> 2

Depending on the T1 you're using, you may need to set Master/Slave and provide clocking at one end.

George

mikej412

And if you are going to test 2 routers with frame relay back-to-back, without a router in the middle acting as the frame switch, then you use the no keepalive command to disable lmi and let the interfaces come up. But that's a stupid router trick.

Don't forget to use your show commands to troubleshoot.

ptlinva

Wow!

Thank you everyone for the awesome and kind responses!

georgemc - Yes, I do believe the cables are correct. I used that exact pinout on the first cable. I also read that pin 3 was used as a ground sometimes and I actually used that one to help line up the cables into the connector when making them. Same results either way... But since you mentioned it, I'll look again and make another one.

mikej412 - I was just following Chris's examples and using all the same commands that he was using in his serial configurations. Hence, I'm still learning them. So by removing the command "no frame-relay inverse-arp", do I need to do anything to configure a "full mesh"?

Mike, I also purchased two more routers today (2610s) so I can move forward with the serial configurations and make it through my frame relay sections. Correct me if I'm wrong, but I plan on purchasing a NM-4T (or A/S if they are compatible) for the FRS and (4) WIC-1T's (or 2T's) and corresponding cables for the other routers.

BTW, will a WIC-1T work in a 2801? I believe it will work in the 2610's, the 3620, and the 1841 I have but I'm not sure about the 2801.

I REALLY do appreciate all of your kind advice and will follow-up shortly with my test results.

Thanks again gentlemen! Have a wonderful evening!

Your friend in Virginia,
Paul L.

mikej412

I posted this

mikej412 wrote: »

Cisco Portable Product Sheets

Some of my favorite PDFs are the
Cisco Switch Performance
IOS Packaging
Router Memory
Router Performance
NM/WIC/VWIC Compatibility (the module xref I posted earlier)

The Integrated Service Routers Quick Look is nice if you win the lottery and want to build a home lab with New Equipment like the 1800/2800/3800 series routers.

in the http://www.techexams.net/forums/ccna-ccent/38753-questions-about-different-routers-home-lab.html thread.

The NM/WIC/VWIC Compatibility PDF should tell you which interfaces are supported by most routers. I don't think the NM-4T is supported in the 2600s (especially since they aren't supported in the 2600XMs).

You can test your back-to-back T1 cable by just configuring 2 of the T1 serial ports as point-to-point links with the default hdlc (or ppp if you want) encapsulation.

Then configure your router that is going to act as the frame-relay switch. I posted an old config a couple days ago that should work for most routers using the frame-relay route commands. Somewhere in a 12.1 IOS train they added the connect command which lets you configure a router to act as a frame-relay switch easier and faster. Did Chris show a sample of the frame relay switch using either methods?

You can check out TechExams.Net CCNA TechLab: Configuring Frame Relay

ptlinva

Wow Mike...

You've given me enough to chew on for awhile. I have a few more questions but I'll post them in a new thread. BTW, I started through the techexams frame relay article and I'm definately gaining some new perspective.

Thanks again for everyone for all of thier time. I hope to be able to repay the favor by helping others as well.

Your friend,
Paul L.