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hi all,

today i came across something which i had never seen or experienced before. it was like this.

we have one 3360 router using PRI - E1 controller used as backup (ISDN)

one the other site where the problem was encountered has a 1721 router configured to have one se0 and one bri int, bri int automatically diales if the se0 int is down for x time.

today the se0 went down and bri dialed nd got connected successfully, one of the administrator working on this 1721 router did a "shutdown" on se0 int and i don't know but it was very strange to observe that we lost the connectivity even through this backup isdn(bri).


if we administratively shutdown the se int while the bri int is connected does it effect in this way that the bri int will not be able to connect also or what ? i hope my point is clear.

Hall of Fame Super Silver


What you describe does not make much sense to me. What you seem to be saying is that the remote 1721 has the serial interface configured with backup isdn inteface. When the serial went down the bri established a connection (up to this point it is acting as expected). Then I think you say that the administrator on the 1721 did a shutdown on the serial and it terminated the connection on the isdn. That does not make much sense. If the serial is up and you issue shutdown that will not cause the isdn to establish a connection. And if the serial is down and you shutdown the serial it should not impact the bri.

Is there any chance that the administrator on the 1721 shutdown the bri rather than the isdn? Are there logs on the 1721 that might clarify this?



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