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New Member

ISDN Issue

Hello all,

Would like to know whther the below setup works ??

Primary connection :

Site C connected to Site B ( point-point)

Site B connected to Site A ( point-point)

Secondary connection:

Site C connected to Site B (ISDN)

Site B connected to Site A (ISDN)

Now , I have a scenrio where the site B will be completly isolated.Im need of connectivity to Site C on ISDN.

Site C Dialer 1 to Site B ( Floating route with AD 200 )

Site C Dialer 2 to Site A ( Floating route with AD 220 )

Will this configuration makes Site C reachable during Site B isolation without manual intervention ?? if not please suggest !!

Routing protocol EIGRP !!

Thanks in advance.

Hall of Fame Super Silver

Re: ISDN Issue

Hello Raghavan,

if you provide the return path floating static routes the answer can be yes

Site C will try to use Dialer1 to SiteB.

How will site B knows to reach SiteC subnets via ISDN ? siteB requires a floating static route.

But If Site B is really isolated even at ISDN layer what will happen ?

If Dialer1 state is spoofed to up/up the SiteC wil try to use it and stay there

If Dialer1 is not spoofed siteC will go to dialer2

Best Regards


New Member

Re: ISDN Issue


Thanks for your reply , I guess the dialer 1 in site C will be in spoofing state during site B isolation.

Is there any way I can make the Site C to take the Dialer 2 to Site A automatically ??

Thanks in advance !!!