4 Replies Latest reply on Feb 13, 2013 3:08 PM by smartd

    DHCP server scan


      I'm running IPAM 3.0 and am having trouble updating IPAM with my DHCP scope definitions.


      I had the following scopes originally defined on the DHCP server and when I first added the server to IPAM, it scanned it and picked them up and everything looked good.



      Time passes, things change, we now need a /24 subnet in place of the two /25s, so I delete the two scopes on the DHCP server and create a new one:



      I let IPAM do its default scans every 4 hours, and nothing changes to indicate it's registered this change.

      So I go in and delete the two scopes in IPAM, and manually run a DHCP server scan. Result... nothing shows up in "Discovered Subnets".

      The two /25 subnets are no longer in my subnets list in IPAM.


      Am I missing a step somewhere or misunderstanding the process?


      What should I do for IPAM to pick up the newly defined scope/subnet?




        • Re: DHCP server scan

          Hi jmosh,


          When you delete scopes form DHCP server, they should appear as unreachable after next scan.


          The scope '/24' which merges both previous '/25' scopes acts like a new scope (from IPAM’s point of view).

          This “new” scope can be found after successful scan in list of found scopes:

          DHCP & DNS Management -> scopes tab card -> Add New -> Found DHCP Scopes


          IPAM Settings -> Add discovered DHCP Scopes to IPAM

          Ondrej Hruska,

          IPAM Dev. Team

            • Re: DHCP server scan

              Hi Ondrej,


              Thanks for the response. Unfortunately when I do a successful scan of the DHCP server, then go to Add New -> Found DHCP Scopes, the list there doesn't show the new scope. Instead it just lists the two scopes that I deleted from IPAM (and interestingly, the date in the Found column is the date of the original scan when I first added the two /25 subnets).


              I've tried restarting all the IPAM services on the server in case something needs refreshing but still no luck.



            • Re: DHCP server scan

              I've been working on cleaning up our IPAM.  I have currently over 16000 IPs in it, so its a big job.

              1. We will often take a /24 subnet, and break it into a /25 plus some /27 subnets.  We usually see this when they delete the old subnet and add the new one.

              The old subnet will have a grey icon when deleted.  When you delete the scope, it will ask to delete the subnet, which it what we normally want.  HOWEVER, sometimes there are manually entered addresses in there.  If you delete the scope, these get deleted.  You can manage the new /25 scope but these entries are gone.


              What is need is a way to migrate/reconcile used addresses and comments/attributes from one scope to another, so manual entries are not lost.


              2.We will often close sites for long periods of time, or sell sites.  What is often done is to deactivate the subnet.  In this case the icon shows as Cyan.  We will delete these scopes, and their associated subnet.  The problem is that deactivated subnets come back in the next scan, AND show up in the unmanged subnet/scope list.


              We need a option to IGNORE deactivated scopes, and for them NOT to be included in the unmanaged subnet list.


              3. I'd like to hide items in the unmanged subnet list that I NEVER want to manage.  I'd like a hide option that can be toggled on an off to hide these from the list.  Similar to ignoring in Node Management.


              Note: It would be nice to have a legend for scope icon colors since this seem undocumented.