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Cisco 1751 T1 question

We have multiple sites in our WAN. We recently installed a new T1 line at a new site. I am new to Cisco and the company won't fork over the money to send me to school, so I have read and learned quite a bit, but I'm having a problem. At the main site (A) with have a Cisco 2600 that has a T1 card and works fine. At the new site (B) we installed a Cisco

1751-V (left over router we had from an old location) I installed a WIC-1DSU-T1-V2 in it. I believe the config is fine. I have sent it to a couple of guys from the phone company and they say it seems ok. The problem is on site A it says the link and protocol are down. On site B it says the line is up and the protocol is down. The question I have is about the cable coming from the WIC-1DSU-T1-V2 to the demarc. I had a RJ45 Cat 5 cable, but somebody told me that I need a RJ48 cable. I looked it up and there are different kinds of RJ48 cables. Can anyone give me any information to help me.

Thanks in advance, Klaki

Reply to
shinjagunjin
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Just to give some more information. All the other sites connected to site A are up and running. We are using 256k of the T1 for our new site.

Reply to
shinjagunjin

RJ-48 (Registered Jack-48) A telephone connector that holds up to eight wires.

It uses the same plug and socket as RJ-45 but has different pinouts.

An RJ48 cable uses shilded twisted pair (STP).

RJ-48C is commonly used for T1 lines and uses pins 1, 2, 4 and 5.

Pin Pair Signal

1 R RX Ring 2 T RX Tip 3 reserved 4 R1 TX Ring 5 T1 TX Tip 6 reserved 7 shield 8 shield
Reply to
Merv

So is this the type of cable I should be using?

Reply to
shinjagunjin

What are you using on the working T1 circuits - HQ or remote ?

Reply to
Merv

Not exactly sure. Sorry, like I said I don't hae much training. I'm hoping through this experience it will give them enough reason to send me off to school. Is there an easy way to tell?

Thanks again Merv

Reply to
shinjagunjin

Looks on the outside of the cable cladding to see if there are any designation of calbe type. If it is CAT 5 it will usally be stamped on the cladding

Reply to
Merv

I looked at cables coming from an T1 DSU/CSU card on one of our routers that runs to a demarc for the internet and the cable was a Cat 5.

Reply to
shinjagunjin

So you now know that you can get away witha CAT5 cable.

The RJ48 cable being a shield cable would be the "right" cable to use but you know the CAT 5 will work.

I would check the router interface for the working T1 that has a CAT 5 cable to make sure that T1 is not having any errors. The command to use is "show interface < interface> "; if it has been some time since the interface was cleared or if the errors counters are high then clear the counters using the "clear counters ".

Make sure you test the CAT5 cable that is being used on the troubled circuit to make sure that calbe is not faulty.

Reply to
Merv

The line seems to be fine. When I do a show interfaces on the Serial I do get a DTE LMI down. I thought this meant that there was something wrong on the FR switch, but the phone people assure me that the circuit and everything is fine.

Reply to
shinjagunjin

Here are the configs:

Site A: ! version 12.1 no service single-slot-reload-enable service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname SiteA ! logging rate-limit console 10 except errors

! ip subnet-zero ! ! no ip finger ! call rsvp-sync ! ! ! ! ! ! ! controller T1 0/0 framing esf linecode b8zs cablelength long gain26 -7.5db channel-group 2 timeslots 1-24 speed 64 ! controller T1 0/1 framing esf clock source internal linecode b8zs tdm-group 6 timeslots 3 ! ! interface FastEthernet0/0 description **** link to Host LAN **** ip address 192.x.x.x 255.255.255.0 duplex auto speed auto ! interface Serial0/0:2 description ***** Link to WAN **** mtu 1600 bandwidth 1536000 no ip address encapsulation frame-relay IETF frame-relay traffic-shaping frame-relay lmi-type ansi ! interface Serial0/0:2.Bdlci point-to-point description **** Link to Site B **** bandwidth 256000 ip address 200.x.x.1 255.255.255.0 frame-relay class 128k frame-relay interface-dlci Bdlci ! interface FastEthernet0/1 description **** Link to Internet Firewall **** ip address 192.x.x.x 255.255.255.0 duplex auto speed auto ! router rip redistribute connected network 192.x.x..0 network 192.x.x.0 network 198.x.x.0 network 199.x.x.0 network 200.x.x.0 network 204.x.x.0 ! ip classless ip route 0.0.0.0 0.0.0.0 192.x.x.x ip route 192.x.x.x 255.255.255.0 192.x.x.x ip route 192.x.x.x 255.255.255.0 192.x.x.x ip route 204.x.x.x 255.255.255.255 194.x.x.x no ip http server ! ! map-class frame-relay 128k no frame-relay adaptive-shaping frame-relay cir 256000 frame-relay bc 2560 frame-relay be 128000 frame-relay mincir 128000 frame-relay priority-group 1 ! map-class frame-relay 512k no frame-relay adaptive-shaping frame-relay cir 512000 frame-relay bc 5120 frame-relay be 256000 frame-relay mincir 256000

Site B: version 12.3 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption ! hostname siteB ! boot-start-marker boot-end-marker ! enable secret 5 *********************** ! mmi polling-interval 60 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 FastEthernet0/0 ip address 192.168.x.x 255.255.255.0 ip helper-address 192.168.x.x. speed auto ! interface Serial0/0 mtu 1600 no ip address encapsulation frame-relay IETF no fair-queue service-module t1 timeslots 1-4 frame-relay lmi-type ansi ! interface Serial0/0.Adcli point-to-point description *** Link to Site A *** ip address 200.x.x.2 255.255.255.0 frame-relay interface-dlci Adlci ! ip classless ip route 0.0.0.0 0.0.0.0 200.x.x.1 no ip http server ! !

Does this help any?

Reply to
shinjagunjin

When you say the T1 circuit at sitre A is fine what do you mean ?

Are there other site that the router at site A is connected to besides side B ?

show interface

show controller t1

show frame-relay map

show frame-relay pvc

! verify that LMI status requests are being sent and received

show frame-relay lmi

Reply to
Merv

SiteA has multiple sites connected to it. All the other sites work fine except SiteB.

I sent you the file to look over.

Reply to
shinjagunjin

check your gmail email

Reply to
Merv

Received your email.

Do you have remote console access to the router at site B

Reply to
Merv

I can drive to the location and I do have internet access over there as well.

Reply to
shinjagunjin

You should capture the output for the same set of commands as you did on the 2600

Reply to
Merv

You should have them now.

Thanks, Klaki

Reply to
shinjagunjin

Kinda hard to to trouble shoot from someone elses e-mail account

Reply to
the_jonesboys_posse

First off, if you see UP/Down on a router, it *generally* means that physical layer is fine, but layer 2 is down. This would be your Frame-Relay settings. 9 times out of 10 I see this issue relating specifically to the LMI not matching, but you'll have to confirm with your telco what LMI you should be using (or just try some different settings and see if it comes up). Also is it s0/0 thats showing up/down or the subinterface?

I'd also play with the clock source. Many times you can set the clock source to be from the network (instead of internal) as the telco generally provides clocking.

Also, I have a side note, not pertaining to your question at all -- I see a few problems with your config. The map-classes setup aren't configured correctly. Your 'bc' and 'be' should be configured in bits not bytes. You can look up how to configure this on cisco's site or send me an email and I can clarify.

Ryan

Reply to
rdymek

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