+ Post New Thread
Results 1 to 7 of 7
Network and Classroom Management Thread, NEW IP RANGE in Technical; Our ISP has changed our IP range for curriculum network so that we can accomodate more clients on the network ...
  1. #1

    Join Date
    Jan 2008
    Posts
    96
    Thank Post
    1
    Thanked 0 Times in 0 Posts
    Rep Power
    0

    NEW IP RANGE

    Our ISP has changed our IP range for curriculum network so that we can accomodate more clients on the network as the old range only allowed 254 hosts (Old IP settings: 10.8.100.0 subnet mask 255.255.255.0/24) which gives us 254 hosts.
    on the new range they have changed our IP address to 10.8.101.0 with a subnet mask of 225.255.252.0/22 which will allow 1022 hosts."
    please guide me step by step how to configure my DHCP and DNS for the new IP range.
    Last edited by Ric_; 14th April 2008 at 07:51 PM. Reason: Nasty markup removed

  2. #2
    StewartKnight's Avatar
    Join Date
    Jun 2005
    Posts
    1,587
    Thank Post
    2
    Thanked 27 Times in 21 Posts
    Rep Power
    30
    This is incredibly simple to do
    Look at this website for a detailed guide.

  3. #3

    Join Date
    Jan 2008
    Posts
    96
    Thank Post
    1
    Thanked 0 Times in 0 Posts
    Rep Power
    0
    I traied to edit the existing scope but i can not edit the subnet mask, it is grayed out for some reasons. any clues?

  4. #4

    Join Date
    Mar 2007
    Posts
    1,752
    Thank Post
    79
    Thanked 288 Times in 219 Posts
    Rep Power
    70
    i dont think you can edit a subnet mask, i beleive you have to recreate the scope.

  5. #5
    User3204's Avatar
    Join Date
    Aug 2006
    Location
    Wirral
    Posts
    769
    Thank Post
    55
    Thanked 66 Times in 62 Posts
    Rep Power
    34
    Are you sure that that is the right IP range ?

    The range 10.8.101.0/22 isn't right, I expect the range has changed to 10.8.100.0/22, which will encompass the old range and the new range from 10.8.100.0 to 10.8.103.255.

    So you can keep using the old range for a while.

    Unless they've changed Windows you will have to create a new DHCP scope.
    Basically:

    1. change the subnet masks on the servers to handle the new 255.255.252.0;
    2. create a new scope in the DHCP server, but leave it disabled. Copy the details from the existing scope;
    3. change the existing scope lease time to 4 hours or something short;
    4. at the end of one day disable the old scope, and enable the new one;
    5. wait for next day, and hopefully noone screams;

  6. #6

    Join Date
    Jan 2008
    Posts
    96
    Thank Post
    1
    Thanked 0 Times in 0 Posts
    Rep Power
    0
    Quote Originally Posted by User3204 View Post
    Are you sure that that is the right IP range ?

    The range 10.8.101.0/22 isn't right, I expect the range has changed to 10.8.100.0/22, which will encompass the old range and the new range from 10.8.100.0 to 10.8.103.255.

    So you can keep using the old range for a while.

    Unless they've changed Windows you will have to create a new DHCP scope.
    Basically:

    1. change the subnet masks on the servers to handle the new 255.255.252.0;
    2. create a new scope in the DHCP server, but leave it disabled. Copy the details from the existing scope;
    3. change the existing scope lease time to 4 hours or something short;
    4. at the end of one day disable the old scope, and enable the new one;
    5. wait for next day, and hopefully noone screams;

    I realised the error and I called our ISP and asked them to only change the subnet maske from 255.255.255.0; to 255.255.252.0 and leave the ip address s 10.8.100.0 they have realised thier mistake and changed the ip back to 10.8.100.0. Now I tried to create a new scope it comes up with an error message saying "this is a wrong scope or the scope already exists" though this is not the exact wording of the error but it is something in the same line. I disabled the existing scope and then tried to create a new one it still did not allow me.

  7. #7
    User3204's Avatar
    Join Date
    Aug 2006
    Location
    Wirral
    Posts
    769
    Thank Post
    55
    Thanked 66 Times in 62 Posts
    Rep Power
    34
    Bugger,

    I have only ever changed scopes from one range to a completely different range (10.10.y.z went to 10.0.y.z etc) and this works, I kinda assumed it would work. But I expect overlapping ranges on the same server ain't something anyone should do.

    Do you have another server you could setup as a DHCP ? DHCP doesn't take up a lot of processor on the server, try another DC.

    If not, you will have to delete the original range to create the new one.

    Sorry.

    I have two DHCP servers that can give out IP addresses in the same range, it's setup for redundancy, supposedly.

SHARE:
+ Post New Thread

Similar Threads

  1. Adding another IP Range to DHCP
    By Nick_Parker in forum Windows
    Replies: 35
    Last Post: 3rd March 2008, 12:36 PM
  2. Move DC to new IPv4 Range
    By Gatt in forum Windows
    Replies: 12
    Last Post: 25th August 2007, 02:50 PM
  3. Extending IP Range
    By Grommit in forum Windows
    Replies: 12
    Last Post: 17th November 2006, 04:59 PM
  4. Replies: 2
    Last Post: 12th October 2006, 12:44 PM
  5. Net Support add a new product to their range
    By Dos_Box in forum General Chat
    Replies: 2
    Last Post: 15th June 2006, 09:34 PM

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •