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Client on one WLC, not getting DHCP from second WLC

I have a 2504 WLC and its internal DHCP Server configured to serve wireless clients.
 
I have just installed and configured virtual WLC.
I have setup via FlexConnect groups (as the vWLC does not do local mode) that the DHCP server address is the 2504.
 
A client connect to an AP associated to the vWLC does not obtain an IP Address.
 
The IP address of the 2504 is 10.72.14.5 /24 and 172.16.0.5 /22
The IP address of the vWLC is 10.72.14.6 /24 and 172.16.0.6 /22
 
Here is the edited output from a vWLC CLI command, debug client:
 
DHCP selected relay 1 - 172.16.0.5 (local address 172.16.0.6, gateway 172.16.0.5, VLAN 172, port 1) 
DHCP transmitting DHCP DISCOVER (1) 
DHCP   op: BOOTREQUEST, htype: Ethernet, hlen: 6, hops: 1 
DHCP   xid: 0xc624a97f (3324291455), secs: 2560, flags: 0 
DHCP   chaddr: d8:b3:77:57:2b:a1 
DHCP   ciaddr: 0.0.0.0,  yiaddr: 0.0.0.0 
DHCP   siaddr: 0.0.0.0,  giaddr: 172.16.0.6 
DHCP sending REQUEST to 172.16.0.5 (len 390, port 1, vlan 172) 
DHCP selecting relay 2 - control block settings: 
dhcpServer: 0.0.0.0, dhcpNetmask: 0.0.0.0, 
dhcpGateway: 0.0.0.0, dhcpRelay: 172.16.0.6  VLAN: 172 
DHCP selected relay 2 - 10.72.14.5 (local address 172.16.0.6, gateway 172.16.0.1, VLAN 172, port 1) 
DHCP transmitting DHCP DISCOVER (1) 
DHCP   op: BOOTREQUEST, htype: Ethernet, hlen: 6, hops: 2 
DHCP   xid: 0xc624a97f (3324291455), secs: 2560, flags: 0 
DHCP   chaddr: d8:b3:77:57:2b:a1 
DHCP   ciaddr: 0.0.0.0,  yiaddr: 0.0.0.0 
DHCP   siaddr: 0.0.0.0,  giaddr: 172.16.0.6 
DHCP sending REQUEST to 172.16.0.1 (len 390, port 1, vlan 172) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP received op BOOTREQUEST (1) (len 345,vlan 14, port 1, encap 0xec03) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP (encap type 0xec03) mstype 0ff:ff:ff:ff:ff:ff 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selecting relay 1 - control block settings: 
dhcpServer: 0.0.0.0, dhcpNetmask: 0.0.0.0, 
dhcpGateway: 0.0.0.0, dhcpRelay: 172.16.0.6  VLAN: 172 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selected relay 1 - 172.16.0.5 (local address 172.16.0.6, gateway 172.16.0.5, VLAN 172, port 1) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selecting relay 2 - control block settings: 
dhcpServer: 0.0.0.0, dhcpNetmask: 0.0.0.0, 
dhcpGateway: 0.0.0.0, dhcpRelay: 172.16.0.6  VLAN: 172 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selected relay 2 - 10.72.14.5 (local address 172.16.0.6, gateway 172.16.0.1, VLAN 172, port 1) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selecting relay 1 - control block settings: 
dhcpServer: 0.0.0.0, dhcpNetmask: 0.0.0.0, 
dhcpGateway: 0.0.0.0, dhcpRelay: 172.16.0.6  VLAN: 172 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selected relay 1 - 172.16.0.5 (local address 172.16.0.6, gateway 172.16.0.5, VLAN 172, port 1) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP transmitting DHCP DISCOVER (1) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP   op: BOOTREQUEST, htype: Ethernet, hlen: 6, hops: 1 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP   xid: 0xc624a97f (3324291455), secs: 3328, flags: 0 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP   chaddr: d8:b3:77:57:2b:a1 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP   ciaddr: 0.0.0.0,  yiaddr: 0.0.0.0 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP   siaddr: 0.0.0.0,  giaddr: 172.16.0.6 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP sending REQUEST to 172.16.0.5 (len 390, port 1, vlan 172) 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selecting relay 2 - control block settings: 
dhcpServer: 0.0.0.0, dhcpNetmask: 0.0.0.0, 
dhcpGateway: 0.0.0.0, dhcpRelay: 172.16.0.6  VLAN: 172 
*DHCP Socket Task: Sep 25 20:01:44.149: d8:b3:77:57:2b:a1 DHCP selected relay 2 - 10.72.14.5 (local address 172.16.0.6, gateway 172.16.0.1, VLAN 172, port 1)
 
 
It looks to me from this debug output that the vWLC does not know the IP address of the DHCP server.
I have looked and looked at I feel that I have the DHCP server’s address installed correctly.
 
Comments? Suggestions? Opinions? Flames?
Everyone's tags (1)
2 ACCEPTED SOLUTIONS

Accepted Solutions

the vWLC wouldn't and doesn't

the vWLC wouldn't and doesn't need to know the address of your DHCP server. The AP being in FlexConnect mode is going to bridge the packet to the wire locally.

Your L3 interface at the site should have an ip helper address configured that points to the DHCP server that has a scope for the subnet.

That being said, I wouldn't use the 2504 as the DHCP server for clients that aren't going to be passing through it. The WLC DHCP server is implemented for connected clients and is not fully functional.

You'd be better served by using your MSFT server or configuring the scope on a local switch or router.

HTH,

Steve

HTH, Steve ------------------------------------------------------------------------------------------------ Please remember to rate useful posts, and mark questions as answered
Hall of Fame Super Silver

Steve is right!!! You will

Steve is right!!! You will not be able to use any WLC as a dhcp server. The dhcp server for a particular WLC is strictly for the use on that WLC only, for access points and wireless users.  Your 2504 will not hand out dhcp to other users, wireless or wired.

Scott

-Scott
*** Please rate helpful posts ***
2 REPLIES

the vWLC wouldn't and doesn't

the vWLC wouldn't and doesn't need to know the address of your DHCP server. The AP being in FlexConnect mode is going to bridge the packet to the wire locally.

Your L3 interface at the site should have an ip helper address configured that points to the DHCP server that has a scope for the subnet.

That being said, I wouldn't use the 2504 as the DHCP server for clients that aren't going to be passing through it. The WLC DHCP server is implemented for connected clients and is not fully functional.

You'd be better served by using your MSFT server or configuring the scope on a local switch or router.

HTH,

Steve

HTH, Steve ------------------------------------------------------------------------------------------------ Please remember to rate useful posts, and mark questions as answered
Hall of Fame Super Silver

Steve is right!!! You will

Steve is right!!! You will not be able to use any WLC as a dhcp server. The dhcp server for a particular WLC is strictly for the use on that WLC only, for access points and wireless users.  Your 2504 will not hand out dhcp to other users, wireless or wired.

Scott

-Scott
*** Please rate helpful posts ***
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