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Cisco ONS 15454 E3-12 & E3/DS3 loopback testing

Unanswered Question
Jun 23rd, 2008
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I was wondering if it was possible to daisy chain all the ports (with a hard loop on the last port) on the FMEC E3/DS3 and create circuits between the looped ports in order to perform BER testing on all the E3 ports.

I set that up and connected my test set, but when start sending a signal I end up getting a LOF alarm.

Does anyone have any ideas on what my problem may be and how I would go about performing my test for all the E3 ports?

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Well, there is some info that is needed. What software version are you running? How are the circuits built? In one place you say they are daisy-chained and in another you say the circuits are looped.

I am not familiar with the E3 as we just use DS3s, but here is what I have done.

First, daisy chain the circuits on the backplane (1 out -> 2 in, 2 out -> 3 in, ... , 11 out -> 12 in). Then put an external loop on all 12 ports using CTC (Card view > Maintenance tab > Loopback). The test set output connects to port 1 in and the test set input connects to port 12 out. You should be able to run your test then.

tomlin Thu, 07/03/2008 - 16:15
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based on your test set-up.. did you create circuits between all the ports and then use a physical loop (fiber connections between the ports) on all the ports?

I have it set up with circuits on the backplane and physical loops in the following manner:

test set -> port 1

port 1-> port 2 (VC3 circuit)

port 2-> port 3 (physical loop)

port 3-> port 4 (VC3 circuit)

port 4-> port 5 (physical loop)

port 5-> port 6 (VC3 circuit)



port 12 -> port 12 (physical loop)

When i have this set up and traffic running from my test set , i keep getting LOF alarms on my test set.

However for some reason it works for only 2 ports... anything past 2 ports seems to be unstable and i get alarms..

Any ideas?

bennyjohn Sat, 06/28/2008 - 18:10
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first try to do with one port then try to continue with daisy chain,It should work


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