WLC DHCP question

Hi all
Is it possible to issue a static IP address to a user using the WLC's built-in DHCP server? Each time I connect to a different WLAN and then reconnect to the WLC WLAN, I get a different IP address, even though I've reconnected before the lease time for the IP is set to expire.
Our code version is 4.0.217.0, and the WLC is installed into a 2811.
Thanks

Anthony,
As fas as I am aware in your version of code - no. according to:-
http://www.cisco.com/en/US/docs/wireless/controller/4.0/configuration/guide/c40wlan.html#wp1108097
HTH.

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I don't need introduction guides. But clear few lines of instructions.
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RL69,
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Right?
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"When you hit a wrong note it's the next note that makes it good or bad". Miles Davis

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Hi,
I configured WLC as DHCP server and is working fine when connected to 3750 core switch. The AP's and clients are getting IP address.
When the same WLC is connected to 6500 , the DHCP is not working from WLC . The same port of 6500 switch is verified by connecting a 3750 switch as dhcp server and AP as well as clients are getting IP.
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Dear Surendra,
Please see the answers in line.
1.As per your previous post, if we connect WLC to 3750 core everything works fine.. so in this case, i assume that we have INTERFACE VLAN on the switch and then the management interafce on the WLC are in the same subnet?? correct??
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2. Similarly, if we swap the 3750 with 6500, it doesnt work.. in this case.. have you created the interface vlan on the 6500 in the same subnet as that of management interface of the WLC??
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Or
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"Yes all are in the same subnet"
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Regards,
Savad

Cisco Anchor WLC DHCP sever

Two question related to Anchor WLC.
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2) How session time out is related to DHCP lease? Whenever session time out if reaced client must re authenticate to WLC but does it also re authenticate when DHCP lease is about to expire (Renewal ). Appreciate if you can share any facts related to session time out and DHCP lease on Anchor WLC.
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1) AFAIK, it's not the dhcp server's job. The client knows for how long his dhcp lease is valid and will (most OS implementation) at 50% of the lease time ask to extend that lease.
2)When the WLAN session timeout is reached, the client has to completely reconnect, so this is again OS-specific behavior but most likely the client will send a DHCP_REQUEST, i.e. requesting the same ip it had before and most likely the DHCP server will accept that re-usage. It is possible that a client assumes it can re-use the same ip without sending any dhcp packets. In this case, DHCP server doesn't care (address is still leased) and it depends if the WLC has "DHCP required" configure or not on the ssid.
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Hope this clarifies.
Nicolas
===
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WLC DHCP Settings - Under Dynamic Interface configuration

Hi Guys,
If I have a dynamic interface that is connected to a subnet where the router interfaces have DHCP servers configured under the helper address commands, do I need to configure the DHCP fields under the dynamic interface configuration?
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Ken, the DHCP address under the dynamic interface, is the address the WLC will unicast the DHCP request to when a client tries to use that interface. Under normal operation this address is needed. There is a way to get the WLC to bridge the packet to the wire so that it is a broadcast instead of a unicast packet. CLI command is config dhcp proxy disable.
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Steve

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Dears,
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If Buidling X users want to talk to building Y Users, then how Control & Data Traffic flow will happen between Buidling X & Y. Would all the traffic will go to Primary WLC from Bldg X APs first and then it will be Re Routed back to Buidling Y APs? Can i achieve direct switching between Bldg X&Y APs without going toward WLC?
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If Building X & Y Users want to access the Internet, how would be traffic flow? Would the traffic from X&Y AP will go tunnel all the traffic towards WLC and then it will be routed to Internet gateway?is it possible for Bldg X&Y AP to directly send traffic towards Internet Gateway without going to controllers?
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I have planned to put WLC at physically different locations in different DC A & B. Is it recommended to have such a design? What would be the Failover traffic volume if Primary WLC goes down and secondary controller takes over?
Like I mentioned... earlier, the two HA WLC has to be on the same layer 2 subnet in order for you to use HA. The guide mentions an Ethernet cable to connect both the HA ports on the WLC.
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Help out other by using the rating system and marking answered questions as "Answered"

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I configured on my WLC 5508 a new Interface & VLAN . The WLC act as DHCP Proxy.
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Regards

Hi,
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add the VLAN into the WLC controller wth a new SSID and Interface for this VLAN.
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Regards

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WLC "DHCP Option 82 Remote Id field format"

On WLC, does "DHCP Option 82 Remote Id field format" show client hostname on wlc monitor

Hi Jonathan with sub option 2, from your example D is the node identifier.
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sub option
length
node identifier
port type
interface number
vlan id
For normal pad format it should contain
sub option
length
circuit
length
vlan id
interface number
-Tom
Please mark answered for helpful posts

5508 DHCP questions, 2 seperate DHCP's/subnet's possible?

I have my 5508 setup so that the management/APmanagement port is connected to a switch on vlanXX unsing port 1 active and 2 as failover.
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The Guest Wlan is not picking up a DHCP address and i'm guessing that that is because its sending the request across the management interface? which has no route to the Guest switch with the dhcp server?
How can i get the guest lan to work with a seperate DHCP server on a different subnet?

Hi Eric,
I wanted to add a few additional informational points that may help you understanding proxy and not to proxy.
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The managment interface is not in play UNLESS you use the WLC AS A DHCP SERVER.
Hope this helps ...
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
‎"I'm in a serious relationship with my Wi-Fi. You could say we have a connection."

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I have one question regarding the redundancy feature for two WLC 2106. We have installed on a customer site 2 WLC's 2106 and 6 AP's. Primary and Backup WLC works fine. No the customer asks the question if there is a option to copy the guest access wlan user from the primary controller to the backup controller? The lobby user activates a new user on the primary controller and if the primary controller fails, then the user did not get access to the wlan guest network.
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Hi Jerry,
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Thannks

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Hi All
Can anyone give me a definitive answer to this question please?
If you are using a pair of wireless LAN controllers configured with primary and secondary controllers for the access points and the primary controller fails - do the access points reboot before associating to the secondary controller. I can't see why they would need to but documentation suggests they do.
Additionally, has anyone significantly reduced the failover time? If so, what is the lowest practical failover time. I know the actual failover time can be reduced to 3 seconds but I think that is likely to cause other problems.
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Regards
Roger

As far I know, In this case the AP does not reboot, only changes its lwapp status to discovery and begins with the discovery proccess.
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Best Regards.

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On rv110w, I have 4 vlans.
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Many thanks for providing related info.

When time was set for 5 minutes, after 10plus minutes, the Networking-LAN-DHCP Leased clients shows a total of 50 (max) clients for VLAN3 and there should have been only 2 connected.
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Multisite in same town design.
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Thanks Scott,
so what I had setup before was under each WLAN, was each the interfce pull down to the interface vlan. I have now changed that to management and setup AP groups, each with the site's data and voice vlan defined under the AP group WLAN tab. So instead of the multiple SSID listed, now only two are listed.
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WLC DHCP Proxy - To Do or Not to Do?

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WLC DHCP question

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