How to connect two Cisco 1721 router together?

workfrom925

I finally start to mess around my Cisco hardware purchase. I'm doing Cisco NetAcad Lab 1.5.1 Cabling a Network and Basic Router Configuration.



I have two Cisco 1721 routers. Each router has a T1CSU/DSU WIC installed. With the "Show ip int br" command, R1 shows:

R1(config-if)#do show ip int br
Interface IP-Address OK? Method Status Protocol
Async1 unassigned YES unset down down
FastEthernet0 192.168.1.1 YES manual up down
Serial1 192.168.2.1 YES manual down down
R1(config-if)#


R2 shows:

R2(config-if)#do show ip int br
Interface IP-Address OK? Method Status Protocol
FastEthernet0 unassigned YES unset administratively down down
Serial0 192.168.2.2 YES manual down down
R2(config-if)#

I believe Serial1 on R1 and Serial0 on R2 are the T1CSU/DSU ports. So I used a cross-over cable to connect the two T1 port together. But as you as see, both their status and protocal are down. What's wrong and what's missing here? Thanks.

Christopher Dobkowski

1st. Use the command "show int controller " followed by the interface, in this case serial1 on R1 and check if it's DCE or DTE... if it's DTE, then it's wrong cable end that u inserted.

2nd. Set the clock-rate on the DCE side..

3rd. (OPTIONAL, but I don't think it's the case here) Check if it's using the same Layer 2 encapsulation as the R2... PPP - HDLC (default) - Frame Relay..

workfrom925

After some research on the web. It seems I can't insert a regular cross-over cable into these T1CSU/DSU ports. It seems that they require a T1 Back-to-back Cross-over cable like this one: 1 ft Back to Back Cisco T1 E1 WIC1 DSU T1 Crossover Cable | eBay Do I have to get this cable?

Right now the "show controller serial1" command output below on R1 does not tell me its DCE or DTE status.

R1#show controllers serial1
Interface Serial1
Hardware is PowerQUICC MPC860 with Integrated FT1 CSU/DSU module
TX and RX clocks detected.
idb at 0x813FE214, driver data structure at 0x81405880
SCC Registers:
General [GSMR]=0x2:0x00000030, Protocol-specific [PSMR]=0x8
Events [SCCE]=0x0300, Mask [SCCM]=0x001F, Status [SCCS]=0x03
Transmit on Demand [TODR]=0x0, Data Sync [DSR]=0x7E7E
Interrupt Registers:
Config [CICR]=0x00365F80, Pending [CIPR]=0x00008000
Mask [CIMR]=0x60204400, In-srv [CISR]=0x00000000
Command register [CR]=0x640
Port A [PADIR]=0x0000, [PAPAR]=0x0F0F
[PAODR]=0x0000, [PADAT]=0xABFB
Port B [PBDIR]=0x0380F, [PBPAR]=0x0D00E
[PBODR]=0x00000, [PBDAT]=0x2075C
Port C [PCDIR]=0x008, [PCPAR]=0x000
[PCSO]=0x080, [PCDAT]=0xFE6, [PCINT]=0x000
Receive Ring
rmd(FF003130): status 9000 length 60C address 363C124
rmd(FF00313: status 9000 length 60C address 363BAA4
rmd(FF003140): status 9000 length 60C address 363B424
rmd(FF00314: status 9000 length 60C address 363ADA4
rmd(FF003150): status 9000 length 60C address 363A724
rmd(FF00315: status 9000 length 60C address 363A0A4
rmd(FF003160): status 9000 length 60C address 3639A24
rmd(FF00316: status 9000 length 60C address 36393A4
rmd(FF003170): status 9000 length 60C address 3638D24
rmd(FF00317: status 9000 length 60C address 36386A4
rmd(FF003180): status 9000 length 60C address 3638024
rmd(FF00318: status 9000 length 60C address 36379A4
rmd(FF003190): status 9000 length 60C address 3637324
rmd(FF00319: status 9000 length 60C address 3636CA4
rmd(FF0031A0): status 9000 length 60C address 3636624
rmd(FF0031A: status B000 length 60C address 3635FA4
Transmit Ring
tmd(FF0031B0): status 0 length CAFE address 0
tmd(FF0031B: status 0 length CAFE address 0
tmd(FF0031C0): status 0 length CAFE address 0
tmd(FF0031C: status 0 length CAFE address 0
tmd(FF0031D0): status 0 length CAFE address 0
tmd(FF0031D: status 0 length CAFE address 0
tmd(FF0031E0): status 0 length CAFE address 0
tmd(FF0031E: status 0 length CAFE address 0
tmd(FF0031F0): status 0 length CAFE address 0
tmd(FF0031F: status 0 length CAFE address 0
tmd(FF003200): status 0 length CAFE address 0
tmd(FF00320: status 0 length CAFE address 0
tmd(FF003210): status 0 length CAFE address 0
tmd(FF00321: status 0 length CAFE address 0
tmd(FF003220): status 0 length CAFE address 0
tmd(FF00322: status 2000 length CAFE address 0

tx_limited=1(2)

SCC GENERAL PARAMETER RAM (at 0xFF003D00)
Rx BD Base [RBASE]=0x3130, Fn Code [RFCR]=0x18
Tx BD Base [TBASE]=0x31B0, Fn Code [TFCR]=0x18
Max Rx Buff Len [MRBLR]=1548
Rx State [RSTATE]=0x0, BD Ptr [RBPTR]=0x3130
Tx State [TSTATE]=0x0, BD Ptr [TBPTR]=0x31B0

SCC HDLC PARAMETER RAM (at 0xFF003D3
CRC Preset [C_PRES]=0xFFFF, Mask [C_MASK]=0xF0B8
Errors: CRC [CRCEC]=0, Aborts [ABTSC]=0, Discards [DISFC]=0
Nonmatch Addr Cntr [NMARC]=0
Retry Count [RETRC]=0
Max Frame Length [MFLR]=1608
Rx Int Threshold [RFTHR]=0, Frame Cnt [RFCNT]=0
User-defined Address 0000/0000/0000/0000
User-defined Address Mask 0x0000


buffer size 1524

PowerQUICC SCC specific errors:
0 input aborts on receiving flag sequence
0 throttles, 0 enables
0 overruns
0 transmitter underruns
0 transmitter CTS losts


R1#

Christopher Dobkowski

Is your router looking like this?

http://www.ebay.com/itm/CISCO-1751V-WIRED-ROUTER-2-WIC1DSUT1-1-WIC1DSU-56k-AND-POWER-CORD-/121087264929?_trksid=p2047675.m1982&_trkparms=aid%3D333005%26algo%3DRIC.FIT%26ao%3D1%26asc%3D177%26meid%3D6712958748534819364%26pid%3D100009%26prg%3D1088%26rk%3D5%26sd%3D150854483828%26

If yes, then yes, you need a T1 back to back cable like the one you showed.

jdballinger

Yes you need a T1 crossover cable to make them talk, since you are using T1 serial cards. If you have the tools lying around to crimp RJ-45 ends, and a few spare end connectors, just do it yourself. Find the pin-out online (use Google Images to search, that works wonders for cable diagrams) and make the cable.

I use primarily WIC-1T/2T cards, but I have a few spare WIC-T1DSU/CSU cards that I use on occasion that I run out of serial connections and need more. You can usually pick those cards up way cheaper than WIC-2T cards on eBay. Consequently, I learned how to make T1 crossover cables and now keep a few around as well for when I need them.

If you don't have the tools to make cable, I highly recommend getting a cheap set, a bag of RJ-45 connectors, and a cheap box of cable. It costs a bit up front, but the ability to make whatever length cable you want, and the knowledge of how to do that, will come in handy down the line.

workfrom925

Christopher Dobkowski wrote: »

Is your router looking like this?

Cisco 1751V Wired Router with 2 WIC1DSUT1 1 WIC1DSU 56K and Power Cord 746320568683 | eBay

If yes, then yes, you need a T1 back to back cable like the one you showed.

This is the card I have.

workfrom925

jdballinger wrote: »

I use primarily WIC-1T/2T cards, but I have a few spare WIC-T1DSU/CSU cards that I use on occasion that I run out of serial connections and need more. You can usually pick those cards up way cheaper than WIC-2T cards on eBay. Consequently, I learned how to make T1 crossover cables and now keep a few around as well for when I need them.

Aren't WIC-1T and WIC-2T cards older than WIC-T1DSU/CSU? Is there any advantage in using WIC-1T or 2T cards than WIC-T1DSU/CSU?

jdballinger

Ah the good old 1760, still a CCNA standby after all these years. You'll definitely need T1 cables for that.

The biggest advantage for me using WIC-2T cards (I have a few 1T cards that came with routers, but I don't usually use them unless I need more connections) is mainly in connection density. I can have two connections off of a single WIC card, as opposed to only being able to have a single connection from a 1DSU card. Since I'm currently doing CCNP studies, I generally have a ton of routers hooked together in some haphazard fashion, and the 2620xm routers that I generally use only allow for two WIC slots (not gonna pay the money for an NM-4A/S for every router).

The T1 cards are just fine for most stuff, but when you get to frame relay studies, you may want to look into WIC-1T cards and either an NM-4A/S or NM-8A/S card for your frame relay switch. It all depends on how may connections you want to have, I'm not sure what your lab setup looks like.

Christopher Dobkowski

workfrom925 wrote: »

This is the card I have.

Then you will have to use the T1 back-to-back cable and connect the T1 CSU/DSU port from R1 to the T1 CSU/DSU port of R2.
Create one yourself if u have the tools, don't spend money. Here's the diagram:

https://kb.sipadvantage.com/kb_upload/image/T1%20crossover.jpg

Christopher Dobkowski

workfrom925 wrote: »

Aren't WIC-1T and WIC-2T cards older than WIC-T1DSU/CSU? Is there any advantage in using WIC-1T or 2T cards than WIC-T1DSU/CSU?

Nope, it's newer technology... The difference is that you use a Serial Cable and the 2T is faster than 1T, and in almost every newer Cisco router you'll find 1T/2T WIC cards rather than ethernet type T1 DSU/CSU..

workfrom925

jdballinger wrote: »

The T1 cards are just fine for most stuff, but when you get to frame relay studies, you may want to look into WIC-1T cards and either an NM-4A/S or NM-8A/S card for your frame relay switch. It all depends on how may connections you want to have, I'm not sure what your lab setup looks like.

You said I might want to look into WIC-1T cards for frame relay switching study. By looking at product pictures on Ebay, a WIC-1T card provides only one serial connection too. So why would WIC-1T card work for frame relay and WIC-T1DSU not?

Just so that we are on the same page, the 2T WIC that you are talking about is this one Cisco WIC 2T Wan 2 Port Card Used 100pcs More Available | eBay , right?

Christopher Dobkowski

workfrom925 wrote: »

You said I might want to look into WIC-1T cards for frame relay switching study. By looking at product pictures on Ebay, a WIC-1T card provides only one serial connection too. So why would WIC-1T card work for frame relay and WIC-T1DSU not?

Just so that we are on the same page, the 2T WIC that you are talking about is this one Cisco WIC 2T Wan 2 Port Card Used 100pcs More Available | eBay , right?

They're both serial interfaces if thats what you're asking.

The WIC-1T would be connected to an external CSU/DSU if you want to use it with a T1. The WIC-1DSU has the CSU/DSU integrated.

The WIC-1T uses a DB60 connector with the Cisco 5 in 1 interface on it. It isn't a type called "DTE/DCE serial cabling". One end will be a DB60 plug and the other end can be a bunch of different types like V.35, RS232 or another DB60 plug for back to back. The WIC-2T uses a smaller SmartSerial plug which actually changes the usage of the pins depending on what type you're using.