New /23 DHCP Scope Issues

giga797 used Ask the Experts™
We were running out of ip addresses on our network, decided to expand our subnet to so we can have another 255 addresses.  Everything works fine for the any users that get dhcp within the  addresses but anyone with cannot access the internet. is there anything else that needs to be configured for those clients to access the internet? we have a cisco 1921 router.
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Rob LeaverSr. Network & Server Engineer

Are you able to ping your default gateway from the .3 computers?

I am assuming you haven't divided your network into vLANs to make this easier?
chances are that you have an access list allowing on the gateway router, which you should change in

Please be aware that access-lists in cisco routers use wildcards.
In that case you have some access-list
which would be changed into

the router itself needs to have its subnet mask changed

hope this helps

Did you change the subnet mask on the NIC of the DNS server (which I assume is your DHCP server), the LAN interface on the router and in the DHCP options?

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max_the_king i changed it according to your suggestion but still no luck below is the settings.  I can ping the devices with the 192.168.3.x from the router. what would the gateway be for the 192.168.3.x clients?

ip dhcp pool
 lease 0 4

interface Vlan1
 description TOLAN
 ip address
 ip flow ingress
 ip nat inside
 ip virtual-reassembly in

ip access-list extended PATv2
 remark PAT ACL v2.5
 permit ip any
yes It is correct.
It should work.
may need a reboot if possible.
sorry i gave you wrong wildcard access-list.

It must be



max_the_king thank you for your help, so i will change it to permit ip any  correct?
permit ip any

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