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mitchcordray
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No IP for Subnets

I have a problem getting dhcp addresses to different subnets.  Current config. is server 2008, Using an HP  Procurve 8212 as our core. I can get addresses on the subnet where the server sets.  Other subnets receive no address.  I have used netmon to see the dhcp request is hitting the server, But never and offers or any other type of DHCP traffic.  The dhcp helper addresses seems right,  And I believe this is correct also since the broadcast is passed to the server from the subnets.  I have removed and rebuilt the scopes several times.  I have also created the same issue using another server,  and server 2003.
What am I missing?
DHCPTCP/IPWindows Server 2008

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mitchcordray

8/22/2022 - Mon
eric-atl

How are these subnets different or separated from the server?  If the requests are hitting the server then they are on the same layer 2 network, if that is so, how should (were you trying to configure) the DHCP server to "know" that an alternate subnet is requesting the lease.  Are these requests being forwarded by a router or another DHCP server?

Please provide:  
  The subnets that you are attempting to use.
  The number of NICs on the server and there IP addressses.
  Basic switch configuration:  VLANs, ACLs
  Location of routers.
JonLambert

Check you DHCP server to see what interfaces it is listening on, and the subnets that you have scopes for.  From your description it sounds like the servers are recieving the DHCP request, but are not responding with an Offer.  Are you sure that the subnets that the DHCP requests that are being fowarded by a Helper  are matching a DHCP scope on the server?
Rick_O_Shay

The DHCP request you are seeing might not have the relay agent info in it which the server needs to determine what subnet it is coming from. There is a global dhcp-relay command for that switch. I believe it is enabled by default but make sure by configuring  "dhcp-relay".
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William Peck
mitchcordray

ASKER
A little more information.  Subnets are 192.168.XXX.XXX.  Vlans are setup on the switch for each subnet. The IP helper address for each subnet can be found in the packet capture at the server.  Each helper address is also the gateway address for the subnet and is functional (statically assighned it works,gets you off the subnet.)
Rick_O_Shay

That sounds like the switch is doing as expected but the server is not. I am not a server guy so I can't tell you what needs to be done to get the server to use the scope for relayed requests properly but it sounds like that is where this is breaking down.
eric-atl

What network is the server listening to?  Is the server configured with more than one interface or multiple network addresses?  What function is the "helper address" providing - if you statically assign an IP (in the subnet that you desire on a machine that is not currently receiving a lease) does the server respond?
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