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RE: WinXP and Valhalla machines do not respond to each other's ping's



> figure out why they are different. Neither mask makes sense based on the
> two ip addresses you provided. If you are using DHCP on both boxes and
> the webstar is supposed to be providing all the information, then the
> subnet masks should be the same.

The set up looks like the ISP is providing the configurations for both and
the webstar is just forwarding the information along. It also looks like
the modem is not routing as opposed to forwarding. This would explain the
different IP subnets, subnet masks, etc.

> based on the addresses provided, you would normally have a subnet mask
> of 255.0.0.0 for a Class A address. They may be subnetting into part of
> the second octet. 255.128, 255.192 depending on if they chop up the
first > two bits. You would have to convert the two addresses to the HEX
> equivalent of each octet to see where the Network mask might end, but the
> ISP should have provided this information or the Cable modem should have
> it set since it would normally pick it up from them via DHCP or DOCSIS???

I know that the cable company here in Toronto uses mac addressing and
allows 2 connects, and the dhcp designations can look just as fubar'ed as
the one's that Phil has shown here.

> OR worst yet, one of your IP's is coming from out of left field from
> another source.
> IE. One is not from your ISP or is an old address. Has all this
> equipment been recently rebooted? You might want to turn it all off
> (except for hub), power up the cable modem and then each system in turn
> and see what the IP/subnet masks get reset to.

I would venture a guess that they'll be just as diverse.

> 1) Find out what the webstar/DHCP source server thinks it is setting
> them to. Its usually via a provided cdrom snmp based windoze program or
> web based interface
>
> 2) check your ISP's provided doc or tech support to find out what they
> should be set to.
>
> 3) Check the network configs of all windoze/linux boxes to make sure
> they are really set for DHCP.

Hmm... if the modem isn't routing and has no firewall configuration (the
webstar Dxl-100 docs don't suggest it's doing either), then the chances of
the 2 machines being able to talk to each other are slim. The ping test
should pass, but if both machines have the default gateway set to the ISP
and the ISP is blocking icmp type 0 packets, there would be no response
anyway. Blocking icmp type 0 doesn't make any sense though, especially on
a dhcp assigned network.

I think Phil's best bet here is to set up the valhalla machine as a NAT
router and issue rfc-1918 ip assignments. It's more secure, less headache
and more flexible than the present situation.

-- 
Keith Mastin
BeechTree Information Technology Services Inc.
Toronto, Canada
(416)696 6070






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