why does this IP conflicts?????

[Guest]

i have this particular confusion:

i have this configuration setup which conflicts:

## NODE 1
IP Address. . . . . . . . . . . . : 10.202.18.8
Subnet Mask . . . . . . . . . . . : 255.255.255.240
Default Gateway . . . . . . . . . : 10.202.18.1
DNS Servers . . . . . . . . . . . : 164.100.3.1
164.100.17.3

## NODE 2
IP Address. . . . . . . . . . . . : 10.202.18.8
Subnet Mask . . . . . . . . . . . : 255.255.255.248
Default Gateway . . . . . . . . . : 10.202.18.1
DNS Servers . . . . . . . . . . . : 164.100.3.1
164.100.17.3

here only difference is that subnet mask is 240 and 248, others remains the
same. well, as these two are on seperate subnets, then why is this IP
conflicts???

can you pls clear me on this issue???
regs
ken

 

[Steve Winograd [MVP]]

i have this particular confusion:

i have this configuration setup which conflicts:

## NODE 1
IP Address. . . . . . . . . . . . : 10.202.18.8
Subnet Mask . . . . . . . . . . . : 255.255.255.240
Default Gateway . . . . . . . . . : 10.202.18.1
DNS Servers . . . . . . . . . . . : 164.100.3.1
164.100.17.3

## NODE 2
IP Address. . . . . . . . . . . . : 10.202.18.8
Subnet Mask . . . . . . . . . . . : 255.255.255.248
Default Gateway . . . . . . . . . : 10.202.18.1
DNS Servers . . . . . . . . . . . : 164.100.3.1
164.100.17.3

here only difference is that subnet mask is 240 and 248, others remains the
same. well, as these two are on seperate subnets, then why is this IP
conflicts???

can you pls clear me on this issue???
regs
ken

You've assigned the same IP address to two different nodes on a
network, which isn't allowed. Assigning different subnet masks to the
two nodes doesn't change that.

Even if you could assign them the same address, none of the nodes on
the network (including those two) would be able to communicate with
both of them.

What's your reason for this configuration? There's probably another
way to accomplish it.
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

 

[Guest]

here.. when i browse the network, this 10.202.18.2/255.255.255.248 dosnt show
up in my 10.202.18.X/255.255.255.240 network. it means that this computer is
in another network. isn't it??? though all these computers are plugged into
one 16 port switch. so, i persume that since this is in another network,
making same 10.202.18.2/255.255.255.240 in my own network will not matter.
but this IP conflict occurs and this makes me think.. what is going on???

are my assumtion correct?

 

[Jim]

here.. when i browse the network, this 10.202.18.2/255.255.255.248 dosnt
show
up in my 10.202.18.X/255.255.255.240 network. it means that this computer
is
in another network. isn't it??? though all these computers are plugged
into
one 16 port switch. so, i persume that since this is in another network,
making same 10.202.18.2/255.255.255.240 in my own network will not matter.
but this IP conflict occurs and this makes me think.. what is going on???

are my assumtion correct?

Why are the masks different? Perhaps that is the problem.
Jim

 

[Guest]

You shouldn't use a IP address for two network interface card.
When you set two computer systems with a IP address under one router, you
will get "IP conflict" message.
If the nodes are under two different router, networks will have a problem to
communicate each other. In this case, network administrator will face a
problem to set them.

 

[AJR]

Not much info - are you getting a "conflict" error or using "conflict" to
address an access problem? Are these "Nodes" two computers - evidently on
the same network (same gateway address) as suggested in Steve's response.
If I remember my network homework - the submask 255.255.255.* is for a class
C network - your IP 10.*.*.* is class A - Yes or No someone!

 

[Steve Winograd [MVP]]

here.. when i browse the network, this 10.202.18.2/255.255.255.248 dosnt show
up in my 10.202.18.X/255.255.255.240 network. it means that this computer is
in another network. isn't it??? though all these computers are plugged into
one 16 port switch. so, i persume that since this is in another network,
making same 10.202.18.2/255.255.255.240 in my own network will not matter.
but this IP conflict occurs and this makes me think.. what is going on???

are my assumtion correct?

I'm sorry, but your assumptions are incorrect, and what you're doing
won't work.

Two nodes connected to the same network switch can't have the same IP
address, regardless of what subnet mask you assign to any of the
nodes.

If you assign the same IP address to two nodes, you'll get the "IP
conflict" error message, and they won't both be able to communicate on
the network, regardless of what subnet mask you assign to any of the
nodes.

In fact, you don't have two different networks. Using two different
subnet masks doesn't create two different networks. You have one
network with conflicting IP addresses.

To have two different subnets on the same network:

1. Use the same subnet mask on all of the nodes.

2. Use different values in the IP address bits that are included in
the subnet mask.

For example, you can define two different subnets using the subnet
mask 255.255.255.240 with the address range that you're using:

Subnet 1: 10.202.18.1 - 10.102.18.15
Subnet 2: 10.202.18.1.16 - 10.102.18.254.

To see why that's true:

11111111 11111111 11111111 1111 0000 = subnet mask

00001010 11001010 00010010 0000 XXXX = Subnet 1
00001010 11001010 00010010 0001 XXXX = Subnet 2

The two subnets are different in the right-most bit of the subnet mask
and identical in the other bits.
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com