A router question

You need to tell the ISP to set up failover routing for this. If they sold you the ISDN as a backup for the T1, they probably set this up at that time.

address

Thank you very much. I thought this ISDN was bought as a backup originally, but I will call the ISP to verify that.

DT

No matter what the ISP says, I would test it for my own curiosity. During a non-critical time, yank the T1. You can then monitor traffic, or just use a dial-up to a different isp to test getting in to your network.

Yes, I absolutely take your advice. I 've always tested everything if possible. That's why I stay too much time in the office during weekends :-)

DT

address

I just found out on the papers that these two lines go to two different ISPs. In this case, will they work with each other to do the fail-over routing ?

DT

I have T1 and a isdn BRI i the same router. I use cost on the route.

ip route 0.0.0.0 0.0.0.0 194.xxx.xx.1 ip route 0.0.0.0 0.0.0.0 194.xxx.xxx.129 200

Regards //Jan

different

fail-over

Are your two gateways 194.xxx.xxx.1 and 194.xxx.xxx.129 in the same or different subnet ?

I may be wrong, what I worry is if the 2nd ISP ( who provides my ISDN ) will route packets to destinations on T1 ( which belongs to 1st ISP ) over the ISDN line. How does it know the T1 line is down ?

DT

Probably not. In this case, you usually need to be using BGP so that your ASN can originate the route advertisement. Although it's not technically prohibited by the protocols, by convention we don't normally allow multiple ASNs to originate the same route.

They are in diffrent subnet.

You can see it int the console log or a syslog

//Jan