changing the subnet mask

Unanswered Question
Aug 1st, 2007
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we're connecting 2 offices via the ethernet port on a 1710 router on the far end and the fastethernet port on our end.

in the original config we planned on using a .248 mask and life is good...the circuit is up and running.

now we have been told that we need to change the mask to .240 to acommidate a few more IPs.

it should be fairly easy/painless to change the mask? right?

Am I missing something?

Any thoughts?

thanks, gary

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Jon Marshall Wed, 08/01/2007 - 06:44
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Hi Gary

Provided the .240 covers the addressing used in the .248, these addresses haven't been used anywhere else and the .240 falls on a natural subnet range you should be absolutely fine to do this.



royalblues Wed, 08/01/2007 - 11:53
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yes as long as you are not having overlapping address, it should be fine.

Remember you might need to update your routing protocol if any with this new information to properly forward packets


garyrivers Wed, 08/01/2007 - 13:00
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Great, thanks.

I don't think the new IPs will overlap. But that is something I will keep in mind.

Thanks for the input. Gary


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