DHCP Issue on a wireless subnet via WLC 3504

[Kim131]

Hey guys,

I have a DHCP issue on one of the subnets 10.0.1.0/22. IP addresses are released well however only with IP addresses between 10.0.1.1-254 are able to access internet ( browse ) the rest of the users up to 10.0.3.254 cannot browse. tried to queries DNS records for a particular domain name using NSLOOPUP but still it is not working.

your assistance, please 

[RoadRunner4k · Accepted solution]

Which software are you running ? and is there an external DHCP handing out the IPs? 

Is the mask correct on clients not able to access internet ? 

Do you got a firewall / router infront to NAT users to internet ? then check if they allow the full subnet of /22

[MHM Cisco World · Accepted solution]

90% of this issue is from the different mask between 
1- GW interface 
2- DHCP Pool 
3- NAT list 
this mismatch lead to this case 
MHM

[Haydn Andrews · Accepted solution]

Sounds like the subnet mask or the gateway is incorrect in the DHCP scope.

Or upstream firewall/ NAT rule has wrong mask for the subnet

[Rich R]

To add to the list of likely mistakes - wrong subnet mask in an ACL.

[Kim131 · Accepted solution]

Hi Guys,

Thank you very much for your responses. it was the wrong subnet mask on the interface gateway on the firewall.  It was /24 instead of /22.

[MHM Cisco World]

You are so welcome 
MHM