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Expanded subnet connectivity problem

I've expanded an IP scope from a /24 to a /22.  I now notice that, although I am getting IP addresses for the entire scope, only the 192.168.0.x range can access (or even ping) the firewall which is at  I believe it must be a setting on the firewall itself, but cannot seem to locate it.  Any ideas?
1 Solution
Mohammed KhawajaManager - Infrastructure:  Information TechnologyCommented:
You need to change the IP subnet for the firewall IP interface that has  If you also have any rules where you have defined /24 then change it to /22.
It would be useful to know a little more about the configuration of the environment, the DHCP server, switches, router and firewall.  

Is the IP Scope on the switch or a separate server?  Is the firewall you mention also the router?  
You will need to configure the router appropriately for this expanded subnet. i.e. you need to configure the physical network in addition to the configuration of the DHCP scope...
a_viking_ventureAuthor Commented:
Thank you all for the posts, but the answer was as suggested by mnkhawaja, a simple matter of forgetting to change the subnet mask on the inside interface on the firewall itself.  Sometimes it's not enough coffee, sometimes it's too much :-)
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