Serial connection to csu/dsu 1

[dloz]

I am connecting cisco 2600's to an externa csu/dsu (100 dcd merlin magix system). The company in charge of phones split a t1 giving me channels 11-24. Both routers are connected with v.35 cables and configured with hdlc but line protocol will not come up. Except when someone make a call across the t1 then it comes up but goes back down when they hang up. I am convinced that it is a problem with the csu/dsu configuration but the company that set it up says it's my problem and that I need to send a rts. Just wondering if anyone has seen this before and has any suggestions for me or the phone co.

 

[Nazgulero]

Hello,

have you tried PPP encapsulation instead of the (Cisco-proprietary) HDLC ? Also, when you say that you have channels 11-24, does that mean you have control over channel 23, which is actually the D-channel ? Can you post the configuration of one of your routers ?

Regards,

GP

 

[dloz]

Yes I have tried ppp still not getting thru to remote router. The phone company says the port that I am connected to has channels 11 -24 connected. I also included the output from show int s0/0

Building configuration...

Current configuration:
!
version 12.0

!
hostname vsashost


!
username vsasremote password 7 1511181E557878
clock timezone EST -5
ip subnet-zero
no ip source-route
ip name-server 192.168.100.1
!
!
!
!
interface FastEthernet0/0
ip address 192.168.100.253 255.255.255.0
ip directed-broadcast
!
interface Serial0/0
ip unnumbered FastEthernet0/0
no ip directed-broadcast
!
router rip
version 2
network 192.168.100.0
!
ip classless
ip route 19.168.101.0 255.255.255.0 Serial0/0
no ip http server
!
!
line con 0
exec-timeout 0 0line con 0
exec-timeout 0 0
password 7 03074819575D72
login
transport input none
line aux 0
line vty 0
password 7 111B1610031719
login
line vty 1 4
password 7 111B1610031719
login
!
end

Serial0/0 is up, line protocol is down
Hardware is PowerQUICC Serial
Description: Connected to Muhlenburg
Interface is unnumbered. Using address of FastEthernet0/0 (192.168.100.253)
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliablility 136/255, txload 1/255, rxload 1/255
Encapsulation HDLC, loopback not set
Keepalive set (10 sec)
Last input 00:12:43, output 00:00:03, output hang never
Last clearing of "show interface" counters 04:15:31
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/2/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
168 packets input, 6252 bytes, 0 no buffer
Received 134 broadcasts, 28 runts, 0 giants, 0 throttles
4289 input errors, 2467 CRC, 1541 frame, 0 overrun, 0 ignored, 281 abort
1951 packets output, 104800 bytes, 0 underruns
0 output errors, 0 collisions, 526 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up

 

[JOAMON]

Reliability does not look what it should be....have same router and this is mine:
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 18/255, rxload 34/255
Encapsulation PPP, LCP Open
NOT GOOD:"4289 input errors, 2467 CRC, 1541 frame, 0 overrun, 0 ignored, 281 abort"
You might also enter no fair-queue on the interface as well.

 

[JOAMON]

Also.....do not see any clocking in config and was wondering if the external csu/dsu is taking care of that for you.

 

[JOAMON]

After looking again I see that your router T1 card thinks it has full T1 bandwidth so clocking would be a good place to start. Should only be 768 if configured and reading correctly. You show 1544 full T1 speed. The external csu/dsu needs to be configured to provide clocking.

 

[JOAMON]

The clocking problem is also probably the cause of the CRC and Frame errors. Once you get the connection running issue the clear counters command and watch it to make sure you do not continue to receive errors.

 

[JOAMON]

You will need to change encap to PPP instead of Cisco propriatory HDLC as you are connecting to non Cisco equipment. Also need to check the external dsu/csu to see how it is configured. B8ZS ESF or something else....

 

[dloz]

I'm told that the clocking on the CSU/DSU is correct. But everything I'm hearing is that it is an issue on third party equipment. Which is what I suspected but thought I would see if any one could see problems on my side. They are both cisco routers running hdlc. No all I have to do is convince the phone guy that it's his problem. will set no fair-queue. Thanks for the help.

 

[JOAMON]

I think you are right that it is not you....The things you need to verify is that their equipment is providing clocking for each line, the line coding, and encapsulation. The encap and line coding must match the router settings. They might be using AMI(robbed bit)line coding were as the default Cisco is B8ZS.