How to removed directly connected route

Unanswered Question
Feb 20th, 2008

Hello all, I have a 6509 with sup 720's. I have a vendor that wants to remove their router and go with a lan to lan VPN. The problem is I disconnect the router which goes to my 6509 and I need to change the route from the directly connected device to point to the firewall. I unplugged the router for a hour and when I do a "sh IP route" it still show is directly connected, null0. Not sure if I can issue a "no ip route, null0"

I have this problem too.
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Paolo Bevilacqua Wed, 02/20/2008 - 08:59

Hi, that is a floating route that kicked in, someone put it there to make sure all trying to 172.15 goes in the bitbucket in lack of better route.

Once you got a better route for your vendor network, it will become preferred or more specific, so no issue and you don't need to do anything.

Hope this helps, please rate post if it does!

Richard Burts Wed, 02/20/2008 - 09:19


It seems to me that we need to know a bit more about this situation. What is the subnet/network that the vendor was using? Was it or was it some part of that range? Is there any other part of that address range that you need to access?

That kind of route x.x.x.x connected to null0 is sometimes the result of a configured summary address. Or it might be a static route configured that way (I see this with some frequency in the configuration of BGP routers) so that the route is always in the routing table. If you could cut and paste that line out of show ip route and post the output we might understand a bit better how it got there.

You mention that a router for the vendor was removed. Was that router running a dynamic routing protocol with your switch? Or were routes statically configured?

If we understood the situation better we could give better advice.



PaulWelc Wed, 02/20/2008 - 10:11

The vendor has PCs and printers on the that connect to our AS400. They state they need that entire range. I swore when I looked yesterday it had a C, now when I look it has a S, so it is static route.

S is directly connected,Null0

Richard Burts Wed, 02/20/2008 - 10:22


Yes that does indicate that it is a static route. You should be able to remove it without much problem and then if you want to configure a new static route which points that network toward your firewall it should be easy to do so.



PaulWelc Wed, 02/20/2008 - 10:27

Rick, I'm guessing I would use "no ip route" do I need to add the null0 to the command?

Richard Burts Wed, 02/20/2008 - 11:18


You could use the complete line including the mask and the null0. Or you could use the address and the mask and it would work. If you try with only no ip route you get an error indicating incomplete command.




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