AP_IP_Address

[mouadmerfouk2021]

Hello community,

I have an issue with access points IP addresses. I have configured APs with static IP addresses but when I connected the APs to the switch they get an IP address from the DHCP in a different subnet than the vlan APs (because the switchport was configured with vlan 1 not the AP management vlan), when I change the switchport configuration to APs vlan, the APs can't get any ip address they also lose the static ones, I want to know if I should reconfigure the APs with static address, or just reboot them.

Thank you for your support.

• Catalyst Access Points

[balaji.bandi]

 I have configured APs with static IP addresses 

Not that i am big fan of AP to be in static address, since AP can move any Switch to get IP address and join WLC.

Couple of things to verify :

1. Is the Static IP reservation with AP and vlan correct.

2. Cross check the MAC Address and reserved IP.

[Tony Rosolek]

How did you assign the static IP addresses?

I don't understand why they shall act as DHCP client or why they shall lose the static address. Maybe something went wrong during configuration of the addresses? 

[Rich R]

Quoted directly from the configuration guide:

"Configuring a Static IP Address on a Lightweight Access Point

If you want to specify an IP address for an access point rather than having one assigned automatically by a DHCP server, you can use the controller GUI or CLI to configure a static IP address for the access point. Static IP addresses are generally used only for deployments with a limited number of APs.

An access point cannot discover the controller using domain name system (DNS) resolution if a static IP address is configured for the access point, unless you specify a DNS server and the domain to which the access point belongs.
Note

If you configure an access point to use a static IP address that is not on the same subnet on which the access point’s previous DHCP address was, the access point falls back to a DHCP address after the access point reboots. If the access point falls back to a DHCP address, enter the show ap config general Cisco_AP CLI command to show that the access point is using a fallback IP address. However, the GUI shows both the static IP address and the DHCP address, but it does not identify the DHCP address as a fallback address."

So using a static IP makes things more complicated and less reliable, and if the AP can't establish connectivity to a WLC (because you've misconfigured it or the switch port) then it will automcatically fall back to DHCP in an attempt to recover connectivity.  So rather than trying to do things the difficult way just use DHCP with option 43.  If you want specific APs to have specific IP addresses (why?) then reserve the IP addresses on your server but that will still be extra hassle if you have to replace an AP.