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Moving a Live Route Interface Instance to another Router

We are planning on moving a route instance on a msfc card lets call it vlan2 to a nexus 7k with same name/vlan-tag and ip address.

I need some input on exactly what type of connection may not recover from a such a hot-cut.

The plan is to do a shut on the "vlan2" interface on the 6509's msfc card (we are in hybrid mode) then bring up the vlan2 interface on the Nexus 7k with same ip (yes, all the trunking an vlans exist and all that jazz, my concerns are really at the layer 3 behavior).

Then do a no interface vlan2 on the msfc, and clear the arp on both routers to help speed things along.  There should be only a small burp using this method with clearing arp to help speed things along.  I expect anywhere from a 10-45 second "burp" while things reconverge.

My concern is on long lived type of connections and how they will react.  I'm not really concerned about things like an ssh or telnet session but more in regards to custom client applications connecting to severs behind this route instance or machines behind this route instance connecting out to servers.

My questions are, if I do a shut on the msfc will that send a RST to any connections flowing through it?  This would work well as then a well behaved application  (I can only hope our inhouse applications are have been coded to be well behaved) will reset and retry.  I am concerned about possibly some applications not truely reseting and staying "open" waiting or the other side.  With what I'm doing, will packets properly flow without a RST through the new router interface that will be brought up on the Nexus 7k. I kinda think that the new router instance when it comes up start seeing flows that haven't gone through the normal SYN ACK process to determine MTU and MSS sizes might get dropped on the floor, until the misbehaved client is restarted through manual intevention to get a SYN ACK through the new router interface.

I'm hoping as long as MTU size is the same things will move over, but I'm not overly confident (the mtu and mss is the same on both router instances).

Can anyone shed any light into this.  I hope I've given enough info.  What we want to do it simply move move a live route instance from one router to another and know of any "gotchas".

Thanks for any and all responses.