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Why is DHCP not beig relayed to this new VLan, on a HP ProCurve Switch?

Pkafkas asked
Last Modified: 2015-09-14

I have a network routing or a DHCP problem.  

We have 2 offices at my work and these 2 offices are linked together with a 10mbs Fiber connection(12 miles a part).  We have a DHCP setup to provide each office with its own IP Address scheme:

Office#1: (Scope: .100 - .175)
Office#2: (Scope: .100 - .140)
We only have 1 DHCP Server which is and that is located at Office#1.

The DHCP Services has been working fine for years; but, yesterday (Friday) DHCP was not being passed to the Office#2 location.  I do not see any warning or errors on the DHCP server.   There is only 1 Ethernet Switch at Office#2 and that switch has the only VLAN that is configured with a 172.20.2.X IP address.  All of the Office#1 ethernet switches have 172.20.1.X IP addresses assigned; hence, DHCP requests (for 172.20.2.X) can only come from Office#2.

Office#2's HP ProCurve Switch IP address is
IP Routing is enabled. is our Firewall which handles the routing rules at office#2.

The Configuration for Office#2 HP ProCurve's ethernet switch is shown below:

Startup configuration:

; J9148A Configuration Editor; Created on release #W.15.14.0012
; Ver #06:04.18.63.ff.35.05:b6
hostname "XX-XXX-48G+POE-2-254"
module 1 type j9148a
trunk 38-39 trk2 lacp
timesync sntp
sntp unicast
sntp server priority 1
no telnet-server
time daylight-time-rule continental-us-and-canada
time timezone 6
ip default-gateway
ip dns domain-name "XXX.com"
ip dns server-address priority 1
ip dns server-address priority 2
ip route
ip routing
interface 1
   speed-duplex 100-full
snmp-server community "MOGL" unrestricted
snmp-server contact "it@mogl.net" location "Mequon Data Closet"
vlan 1
   name "DEFAULT_VLAN"
   no untagged 1,3,6,46
   untagged 2,4-5,7-37,40-45,47-48,Trk2
   ip address
   ip helper-address
vlan 50
   name "Guest_Wireless"
   untagged 6
   tagged 2,4
   no ip address
vlan 100
   name "WAN"
   untagged 1,46
   ip address
vlan 102
   name "Voice"
   untagged 3
   ip address
   qos priority 5
spanning-tree Trk2 priority 4
no autorun
password manager
password operator


The DHCP at Office#1 is working just fine; but, Office#2 leased IP addresses began expiring.  Some PC's at Office#2 still were functional because those leased IP addresses did not expire yet.  I tested this by going to a Windows 7 Pro. PC that was still working (at Office#2) and that was using an IP in the DHCP Scope.  I ran an ipconfig /release<enter> and then an ipconfig /renew<enter> and all of the sudden that PC could not re-connect to the network.  It could not fetch a new DHCP IP address.

It is important to mention that I did update the firmware on the Office#2 switch the day before these DHCP leases started dropping.  But, if I boot the switch back to the previous flash version (stored in the secondary flash slot)  The same problem is present.  We should try to make this work with the new version anyway.

I then added a static IP address to these disconnected PC's, at Office#2, and then those PC's began working just fine.  Hence, I do not believe it is a network routing problem.  Because the telephony is working just fine(which is housed at Office#1) and the data is flowing with Devices that have static IP addresses just fine(Data Replication appliances located at both offices).  Again, the problem is exclusively with devices that were trying to connect to the DHCP at Office#2(ip config /release /renew proved that).  Incidentally one could ping from any device (PC or Switch/Appliance) in Office#2 that had a static IP address.  And Devices in Office#1 could ping Devices in Office#2 just fine.  I do not think routing is a problem.  

Perhaps the "ip helper-address" is not working at the switch in Office#2 or the DHCP scope is not working?  If I am at Office#1 and I try the same ipconfig /release and /renew test on a PC at Office #1, the Office#1 PC's(172.20.1.X) are able to retrieve their DHCP IP address just fine.  

We have users bringing laptops and moving back and forth between Office#1 and Office #2; hence, we will need to get this DHCP problem solved.

My question is what can I do to get DHCP to begin working again at the Office#2 location.
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