Can someone explain the reason for NOT using the "mask" keyword in a
BGP network statement? Ie.

Router bgp 65010
Network 1.1.1.1

VS.

Router bgp 65010
Network 1.1.1.1 mask 255.255.255.0

Thanks,

when you dont "no auto-summary" and want to announce 1.0.0.0/8

jbrunner007@hotmail.com wrote:
Could you please clarify this answer? I don't understand your response

Thank you

Hy,


If you are using the "no auto-summary" keyword:

-You must have a exact match in the IP routing table to appear the
network in the BGP routing table. For example:
- network 1.1.1.1/8 will appear in BGP if network 1.1.1.1/8
appear in the IP routing table.
- network 1.1.1.1/24 will appear in BGP if network 1.1.1.1/24
appear in the IP routing table.


If you are using the "auto-summary" keyword:

-You must have the classfull network or a subnet of this classfull
network in the IP routing table to appear the network in the BGP
routing table. For example:
- network 1.1.1.1/8 will appear in BGP if network 1.1.1.1/8
or 1.1.1.1/10.... exist in the IP routing table.
- network 1.1.1.1/24 will appear in BGP if network 1.1.1.1/24
or 1.1.1.1/26.... exist in the IP routing table.

CIAO

ciscortp@hotmail.com wrote:

Your reply was very informative but it is still unclear what the
difference is between using the bgp Mask keyword and NOT using the mask
keyword in bgp. could you clarify this specifically.

Thanks

Gararda wrote:

Hy,

If you NOT use the mask keyword in the network stament, BGP use by
default the classfull network. For example:
- network 10.1.1.0, the network that BGP install will be
10.0.0.0/8, because the natural
mask of this network is a class A. (remember, you must consider
IP routing table,
auto-summary.....)

I hope this help you.

CIAO.

ciscortp@hotmail.com wrote: