Imelda
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Subnetting ? I can ping different net !
It strange huh..
I have a PC with IP : 10.1.0.19 mask 255.255.255.128 and other PCs with IP : 10.1.0.X mask 255.255.255.0
The computers can ping each other. How it would be ? There is subnetting I put there to difference between this computers. But they can ping each other. Any explaination ?
I have a PC with IP : 10.1.0.19 mask 255.255.255.128 and other PCs with IP : 10.1.0.X mask 255.255.255.0
The computers can ping each other. How it would be ? There is subnetting I put there to difference between this computers. But they can ping each other. Any explaination ?
Do you have gateways defined for the two machines?
If not, then although they are on different subnets, they will have no option but to send the ping packet out on the local segment. The other pc does happen to be on the local segment, so it will reply.
If you want to isolate the two subnets from each other, you really should put them on different cables. And then you would put a router in between in order to connect them up again.
Vijay
If not, then although they are on different subnets, they will have no option but to send the ping packet out on the local segment. The other pc does happen to be on the local segment, so it will reply.
If you want to isolate the two subnets from each other, you really should put them on different cables. And then you would put a router in between in order to connect them up again.
Vijay
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jwalsh88,You said there is address overlapping subnet. Do you mean IP address 10.1.0.1 with mask 255.255.0.0 will detected as a conflicted IP address with 10.1.0.1 with mask 255.255.255.0 ?
I don't think you can have two machines with the *same* address on the physical network - irrespective of netmask. It would seem you need to give the machines that should NOT be able to communicate addresses in different ranges, as outlined by jwalsh88. The netmask sets the "borderline" and the addresses must be in the ranges on either side of this line for communication not to work.
Regards
/RID
Regards
/RID
The only purpose for the subnet mask is so that the machine knows when to look into it's routing table for a route to a machine outside his network range. And to set the broadcast address for his network in his routing table.
When I said overlapping I meant that there were two networks defined and one of the ranges of one network overlaps the range of another. rid is correct, you can never have two devices with the same IP address, regardless of subnet mask, on the same physical wire. The will here each other and conflict.
When I said overlapping I meant that there were two networks defined and one of the ranges of one network overlaps the range of another. rid is correct, you can never have two devices with the same IP address, regardless of subnet mask, on the same physical wire. The will here each other and conflict.
Jwalsh88 and rid sum it up pretty well. Your network should under normal circumstances use only one subnet mask. THat way you are able to segment traffic.
You can use multiple subnet mask lengths but that takes alot of planning and you really need to know what you are doing. In most cases always use the same length of masks.
ASKER
Now I have known the problem that I faced. I decide to accept jwalsh88 as answer. Thank you for all you guys. :)
Regards
/RID