resubnetting scope in DHCP

Discussion in 'Networking' started by oddyager, Oct 2, 2007.

  1. oddyager

    oddyager Diamond Member

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    Hi all,

    I created a scope providing addresses for say 172.17.1.0/26 but now I want to expand that so it now gives 172.17.1.0/24. Is there a way for me to expand it without having to delete the scope and recreate it (I have 50 or so reservations on it)? This scope is live. The subnet mask is greyed out and I can't change it. If this is not possible is there a way for me to backup those reservations and re-import them in?
     
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  3. jlazzaro

    jlazzaro Golden Member

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    there's no way, at least that I know of, to change the mask of a configured scope. you can export the reservations to a tab-delimited text file, but I see no way to import them back.

    you may be able to use dhcpcmd.exe from the resource toolkit to edit the DHCP database located in system32\dhcp...KB 232213
     
  4. oddyager

    oddyager Diamond Member

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    :(

    I'll give that tool a try.
     
  5. oddyager

    oddyager Diamond Member

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    I found this article on the web:

    http://blogs.msdn.com/anto_roc...2005/02/28/381539.aspx

    Running the export command gave me a dump of the reservations and from the looks of it you can re-import them back into dhcp (one of the users mentioned they can do this one scope at a time). I have no idea how this is done as it all looks greek to me.
     
  6. Nothinman

    Nothinman Elite Member

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    Wow, that's a retarded restriction.

    The netsh option shouldn't be too bad, depending on how the export is setup you'd just need to do a search/replace or two to format the file how netsh wants.