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DHCP Broadcasts across WAN
I am bringing up a new WLAN environment and all site LWAP's will receive their DHCP address from the main site that houses the WLAN controllers. I have setup a /24 for the controllers and the LWAP's.
I need some verification and or advice on how I can ensure when a new AP is plugged in that it's DHCP broadcast is sent over the WAN link to the DHCP server here. Seeing as how Routers break up broadcast domains that is a problem, but we have ip helper-address for this.
As it is now, I can ping across the WAN link to the /24 and DHCP server. Now if I create a new vlan interface on the core switch at the other location and set the ip helper-address on it, ping dies and I can no longer reach the /24
I somehow need this because once I start plugging in AP's and trunking ports to the native /24 vlan in question they will need to know how to reach their intended DHCP server.
I am somehow missing something
I need some verification and or advice on how I can ensure when a new AP is plugged in that it's DHCP broadcast is sent over the WAN link to the DHCP server here. Seeing as how Routers break up broadcast domains that is a problem, but we have ip helper-address for this.
As it is now, I can ping across the WAN link to the /24 and DHCP server. Now if I create a new vlan interface on the core switch at the other location and set the ip helper-address on it, ping dies and I can no longer reach the /24
I somehow need this because once I start plugging in AP's and trunking ports to the native /24 vlan in question they will need to know how to reach their intended DHCP server.
I am somehow missing something
Asked:
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1 Solution
These will be in HREAP mode.
I'm going to make Cisco TAC look at this, I showed them yesterday everything and how I have routing up between all sites to this /24 the WLAN Controller sits on.
I actually had one guy tell me yesterday all was well in my config and that the broadcast would go out across the WAN which isn't going to happen without some form of an ip helper
I'm going to make Cisco TAC look at this, I showed them yesterday everything and how I have routing up between all sites to this /24 the WLAN Controller sits on.
I actually had one guy tell me yesterday all was well in my config and that the broadcast would go out across the WAN which isn't going to happen without some form of an ip helper
Sounds good. If you get sick of waiting on TAC, feel free to post configs and "show ip route" on the devices in question.
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If all pings stopped when you created the new vlan, I would guess that there is some type of IP overlap - This could be a duplicated subnet or even two subnets with overlapping host ranges such as 192.168.1.0/24 overlapping 192.168.0.0/23.