IS there anything like interface serial1/0?

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Dec 7th, 2007
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Hi All,

Just upgraded my 2621 series router with a NM 4A/S card, but was surprised to have seen it in the list of interfaces as serials 1/0, 1/1, 1/2 and 1/3 respectfully.

Have i done anything wrong or the card comes in different flavors?. Because i was expecting to see S0/1, 0/2..... and not other way round.

Please if you are knowledgeable to assist i this regard?.


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Richard Burts Fri, 12/07/2007 - 13:39
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Perhaps there is some aspect of your post that I am not understanding correctly. You talk about the addressing being other way round. But as I look at it the real difference between what you expect and what the interface card did was that you expected it to be in slot 0 and it reports that it is in slot 1. But both in your expected addressing and in the card addressing the addressing is based on slot/port where the port numbers indicate the 4 serial interfaces. If I have misunderstood something perhaps you can clarify.



bvsnarayana03 Fri, 12/07/2007 - 21:32
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Rick has nicely explained. Modular devices has many slots & the interfaces are numbered on the basis of cards inserted in specific slot.

This is how to remember, for instance Se0/1 is what is visible in your router. Then the 1st number before (/)i.e. 0 indicates the slot on router & the number to the right of (/) indicate the interface number on card.

So if you were expecting to see "se0/1" but now see "se1/0", then dont worry you have fixed the interface card in slot1 instead of slot0. You may go ahead with your configurations, this has no impact while configuring or operations.

hope that clarifies.

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