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IP Routing Issue

What is the difference between a static route that is linked to an Interface and a static route which is linked with the remote IP Address ??

We have recognized that static routes wich are linked e.g. to a serial interface not work, after we changed the route to the remote ip adress the connection worked.

2 REPLIES
New Member

Re: IP Routing Issue

What is your addressing scheme? The next hop IP address needs to be known by the router, then ARP is used to determine the MAC address to which the packet is to be forwarded. If you are using a class C address with a 30 bit mask, there are only two host addresses per subnet. One of those belongs to the local router and the belongs to the remote router. The local router is able to determine what address is at the remote end by the process of elimination. If you are using, for example, a class C address with a 24 bit mask, the router doesn't know which IP address is the next hop as there are 253 possibilities. In this case, use the remote router's address in your route statement.

Re: IP Routing Issue

If you point a static to and interface it appears as directly connected in the FIB with a cost of 0, if you point it to next hop a recursive lookup is needed to resolve how to get to next hop.

If you have no route back on remote router then the ping will fail, so make sure that your destination knows how to get back to the source.

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