[j-nsp] T1 Loopback

Sean Clarke sean1207 at gmail.com
Wed Jan 27 12:58:42 EST 2010

On 1/27/10 5:54 PM, Abel Alejandro wrote:
> Hello,
> Is it possible to know if there is a loopback on a T1 interface on a
> Juniper?
> If we need to verify if there is a loopback we activate a BERT test and
> if the BERT synchronizes
> then we know there is a loopback but I am wondering if there is an
> easier way to verify this.
> Regards,
> Abel.
> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp

Hi Abel

You should easily be able to put a loop locally or remotely onto an 
interface with the following command ..

set interface t1-0/0/0 t1-options loopback local (or remote)

Then you should be able to run the BERT end to end with a tester.

There is a built in BERT test on the T1 interfaces, however I used this 
some years ago and found whilst it gives an indication of functionality, 
the actual results were a bit inconsistent on certain parameters. I 
believe the functionality of BERT was designed more for the T3 
interfaces, the framers on the E1/T1 PIC's are not great for the BERT.


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