3 Replies Latest reply on Nov 13, 2014 10:23 AM by RichardLetts

    /28 instead of /24

    bullcat

      Hi All,

        Looking for some advice related to a customer whitelist request. We advertise a xxx.xxx.xxx.xxx/24 externally....a customer says this subnet range is too large and wants to use a /28.....My question is, since we are advertising /24 do I need to do anything on my side ( advertise a /28) or since they are accepting only /28 , the larger /24 will cover this?

       

      Thank You,

                  Ron C

        • Re: /28 instead of /24
          peter.ksenzsigh

          Hi Ron,

          I'm not sure I understand your question and the connection of the mask to the whitelist...Currently, UDT whitelist doesn't take a subnet mask into consideration...

          Peter

            • Re: /28 instead of /24
              bullcat

              Hi Peter,

                  Thank you for responding. My concern was, we are advertising a /24 , but, our customer only wants to accept a /28 and I am wondering if the more specific /28 will cause problems. If I advertise the more specific route will it break the /24?

               

              Thank Again,

                              Ron

            • Re: /28 instead of /24
              RichardLetts

              Advertising to whom, how?

              When I see things like this I'm thinking a BGP peering announcement with an external peer, in which case you should announce what you have been allocated/assigned by your local RIR and recorded in the RADB, and you would not want to advertise a smaller block as well as the larger aggregate (a /28 is quite small for a eBGP routing table, many places would filter such a small route)

               

              Advertising routes in BGP has nothing to do with whitelisting in UDT...

               

              Perhaps you could explain what your customer wants to do with whitelisting?