Test 2521 Cisco serial port

[preeda]

Hello,

Now, I have ten 2521 routers returned from branch office, and I need to confirm, whether all the port still function properly. Can anyone here please recommend me, how to test it ??

I used to connect back to back with another router, and test for individual port, but now I have 10 of them. So tired..
Please help !!
Thanks,
Preeda

 

[gbiello]

Do you have an external CSU/DSU? I'd throw one of those into loopback mode and connect it to the serial interface via a standard V.35 cable.
If a "show interface sX" shows "looped", I'd be pretty confident it works.

-gbiello

 

[preeda]

Thank you so much for your response.
I have one more question, when I still keep my current config which is frame relay encapsulation as following, line protocol will shown down(looped). But, when I write erase, and let the router use default hdlc encapsulation and keepalive turn on. Line protocol will back to up (looped). Any thing wrong with this. Now, I am not sure, if I can do local loopback in the production environment to fix the problem.

Thanks you so much for your help !!

interface Serial0
backup interface BRI0
no ip address
encapsulation frame-relay IETF
load-interval 30
frame-relay traffic-shaping
frame-relay class 64k
frame-relay lmi-type ansi
!
interface Serial0.125 point-to-point
description link to xxx
ip address X.X.X.X 255.255.255.252
ip ospf cost 100
frame-relay interface-dlci 125
!
interface Serial0.126 point-to-point
description link xxx
ip address x.x.x.x 255.255.255.252
ip ospf cost 110

Serial0 is up, line protocol is down (looped)
Hardware is HD64570
Description: link to scb_hq line TA
Backup interface BRI0, kickin load not set, kickout load not set
failure delay not set, secondary disable delay not set
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation FRAME-RELAY IETF, loopback not set, keepalive set (10 sec)
LMI enq sent 16, LMI stat recvd 0, LMI upd recvd 0, DTE LMI down
LMI enq recvd 15, LMI stat sent 0, LMI upd sent 0
LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE
FR SVC disabled, LAPF state down
Broadcast queue 0/64, broadcasts sent/dropped 6/0, interface broadcasts 6
Last input 00:00:03, output 00:00:03, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/64/0 (size/threshold/drops)
Conversations 0/1 (active/max active)
Reserved Conversations 0/0 (allocated/max allocated)
30 second input rate 0 bits/sec, 0 packets/sec
30 second output rate 0 bits/sec, 0 packets/sec
83 packets input, 3189 bytes, 0 no buffer
Received 2 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
83 packets output, 3189 bytes, 0 underruns
0 output errors, 0 collisions, 14 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up


Preeda

 

[gbiello]

I'm not sure, but I suspect it has something to do with the line "backup interface BRI0". I have neither seen nor used that command before, but I suspect that interface will only bacome active if an ISDN interface goes down. If you remove that line, the interface will probably come up.

-gbiello