Subnet question

Unanswered Question

We currently have a block of addresses that use a 28 mask and will be changed to a larger block of addresses contiguous with our existing block of addresses. The mask will change to a slash mask of 27. Since we are keeping the original public address in the existing range for the ASA will we have to make any additional changes to our ASA appliance?

I have this problem too.
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Jon Marshall Tue, 06/03/2008 - 06:55


If you are using the public IP addresses you already have for static translations eg

static (inside,outside) netmask

then no you don't need to change this.

If one of the public addresses is assigned to your outside interface then yes you would need to update the subnet mask.

Also i'm assuming that if you are increasing from a /28 to a /27 then your ISP wull route the /27 to your ASA instead of the old /28.


m_zabetian Tue, 06/03/2008 - 10:20

NO just make sure your out side interface IP address change to /27 and default route change to your new default gateway if it is not point to interface


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