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MauricioP's profile

New Contributor

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2 Messages

Monday, November 23rd, 2015 6:00 PM

Static IP routing

Hi,

I became a Comcast Busines becuase my account executive told me that IP routing would not be a probolem.

I am buying a CDIR of 64 IP Visible IP addresses for a specific application.

 

I need the whole CDIR block to be "sent" or routed to my Device (a Cisco Router 7200) since Comcast uses the higher IP address as Gateway, then my block would have to be split and I need to loose at least 4 IP (if using a 255.255.255.252 mask)

 

I've been trying to explain this to Level One and Level two support with no luck. Al I need is that the DPC3939B allows me to "send" an:  IP route like XX.XX.XX.192 mask 255.255.255.192 to 10.1.10.YY (my Cisco's interface) but on the static route page of the Gateway there is no option to "route" the whole CDIR towards my Cisco Router inside the LAN...

I hope someone understand this issue better thjant the guys in the call center....

Thanks!!!!

 

Gold Problem solver

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610 Messages

9 years ago

So a couple of points....

 

First, unless things have changed with Comcast Business recently, the largest block of addresses you can get is a /28 (a block of 13 usable addresses for you, plus the 14th host address in the subnet assigned to the gateway). I believe that for larger blocks, you need to subscribe to fiber service (if you have the Cisco DPC3939B, then you are subscribed to the regular coax-based HFC service).

 

Second, I don't think the routing implementation that Comcast uses will support your method of configuration; you cannot have the gateway announce static IPs for a single device connected behind it. All you can do is either configure devices directly with the Comcast-provided static IPs & connect them to the gateway, or you can enable 1-to-1 NAT which NATs traffic coming from a specific 10.1.10.x device to one of your static IPs. Once again, with fiber service I think your intended confguration is available.

 

Forewarning: I do not have experience with Comcast fiber service, so take that into consideration.

New Contributor

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2 Messages

9 years ago

Thank you train_wreck, as a matter of fact yes, I have been assigned a CDRI of 64 IP addresses, 62 usable.... 

and yes, the issue I am having is that Comcast is not allowing to route the whole block towards my device in order to use the last one (ther greater of the block) as gateway and be able to "subnet" the block, I would neet to sacrifice at least 4 IP and then crate routes within the CDIR, which will be a waste of the IP space. I wouldn't mind having my router using a 10.1.10.X IP if they just let me add a route for the full CDIR block... thanks anyway....

 

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1 Message

5 years ago

good luck most of them dont know what a landline phone is

who ever did comcasts static routing page is a moron