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Resubnetting, what has gone wrong?

I have resubnettet our DHCP scope, going from a 255.255.255.0 to a 255.255.254.0 network in order to have some more IP addresses.

I followed the MS instructions on how to do this, and now I have a scope in this range: 192.168.10.50 - 193.168.11.254, with 192.168.10.1 as the default gateway.

However, I must have done something wrong, as clients receving an 11.x address is unable to communicate properly with 10.x addresses, thus not reaching any server and not reaching the internet either.

So pointers to what I have done wrong would be very much appreciated...

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trenes

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cholthe

ASKER

Fantastic, by doing so I am now able to ping and reach the entire 10.x network. 95% of my problem solved :-)

If you could also assist me in explaining why I am unable to reach the gateway (192.168.10.1) I am a happy man.

Cheers!
Christian

trenes

cholthe,

You mean your 11.x clients can't reach the gateway?
Or do even the 10.x have some problems reaching it.
cheers,

Trenes

cholthe

ASKER

11.x clients can't reach the gateway, 10.x have no trouble.

trenes

cholthe,

On one of the 11.x clients do the following.

route add 0.0.0.0 mask 0.0.0.0 192.168.10.1
And then see if you can reach the gateway.

cheers,

Trenes

cholthe

ASKER

Thanks, added the route, no ping reply i'm afraid.

trenes

cholthe,

Hmm route add 192.168.11.0 mask 255.255.255.0 192.168.10.1 or the last 255 will be 254

cheers,

Trenes

cholthe

ASKER

Thanks again, added route, same error.

The gateway (10.1) is an Isa server 2000, and since everything else works I am starting to think that the problem lies here....

glennbrown2

did you add the new route to the DHCP server's NIC??

browse to the 2nd page of this guide and follow the steps under "One last step"

http://articles.techrepublic.com.com/5100-1035_11-6131003-2.html

cholthe

ASKER

Thanks for the tip glennbrown2, but I haven't created a superscope, I have just resubnetted my existing 255.255.255.0 into a 255.255.254.0 subnet in order for me to have one big subnet instead of superscoping and thus having 2 seperate subnets.

I have followed the instructions here:
http://support.microsoft.com/kb/255999

By doing what trenes wrote in his first reply I was able to have the 11.x clients (same subnet as 10.x), communicate with the 10.x clients, but they are not reaching the 10.1 gateway.

Thanks.

C

glennbrown2

sorry, should have read more carefully :-)

Ok, so from the .11 subnet you can ping all hosts in the .10 subnet EXCEPT for the gateway. Is that right?

Is there a router/switch in between that can't route the .11 network to the .10? Do you need to change the subnet mask on the gateway??

trenes

http://www.microsoft.com/technet/isa/2000/maintain/isalat.mspx

Try this I have not used ISA before so I cannot help you that much on that one.

cholthe

ASKER

Yes, however, I have one "big" 255.255.254.0 subnet now, ranging from 192.168.10.1 - 192.168.11.255.

The hosts that have received, or have manually entered a 11.x address are able to ping and communicate with all other hosts, both with 10.x and 11.x addresses apart from the 10.1, the isa server which acts as gateway.

I have changed the subnet mask on the gateway's internal interface to 255.255.254.0 when I resubnetted.

I am beginning to think that this might be a problem with the ISA server (not accepting 11x clients or something), so I am looking into there.

cholthe

ASKER

Thanks for the tip trenes, the LAT goes from 192.168.10.0 - 192.168.13.255, so I take it this means that this is covered...

I will make a post over at the ISA forums as well...

cholthe

ASKER

Accepting trenes first reply as this answered my initial question, seems like my problem number two is related to the ISA server, and has nothing to do with my resubnetting.

trenes

thank you but I hesitate to accept the points as your problem is not yet away...