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Community Member

ISDN back-up with a different ISP

Dear all,

One of my customer have a 256 kbps leased line with an ISP.They have given 32 ip's to run services for them.He is running 8 online servers with those ip's in his LAN.Now he wish to run ISDN back up with another ISP.I want to know how could I configure ISDN backup on my router.If it was same ISP it would be very easy thing.But the problem here is as ISDN is from different ISP ,I want to know how I could route packets to his LAN which have a different pool of ip's.

Here the problem is ISP1 is advertising his ip's to its uplink provider and when ISDN comes up when leased lines are down ,the systems in the LAN will be down as ISP2 has a different range of IP's.So pls guide me if there is any way through which ,packets can be routed to and back from his LAN when ISDN comes up.

Kindly guide me on this.



Community Member

Re: ISDN back-up with a different ISP

Of course you cannot re-route the Internet! Think of other ways like having the backup with the same ISP with the same address block, or co-locating/hosting content, or maybe a game with the DNS configuration with small TTL! But I don't think there's a way around it in the network and lower layers! Good luck.

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