ip dhcp pool vlan10Pool network 192.168.10.0 255.255.255.0 default-router 192.168.10.1 dns-server 221.110.33.164 221.110.33.132 ip dhcp pool vlan20Pool network 192.168.20.0 255.255.255.0 default-router 192.168.20.1 dns-server 221.110.33.164 221.110.33.132 exit ip dhcp excluded-address 192.168.10.1 ip dhcp excluded-address 192.168.20.1 ip access-list standard NAT permit 192.168.10.0 0.0.0.255 permit 192.168.20.0 0.0.0.255 exit
ip dhcp pool vlan10Pool
network 192.168.10.0 255.255.255.0
default-router 192.168.10.1
dns-server 221.110.33.164 221.110.33.132
ip dhcp pool vlan20Pool
network 192.168.20.0 255.255.255.0
default-router 192.168.20.1
dns-server 221.110.33.164 221.110.33.132
exit
ip dhcp excluded-address 192.168.10.1
ip dhcp excluded-address 192.168.20.1
ip access-list standard NAT
permit 192.168.10.0 0.0.0.255
permit 192.168.20.0 0.0.0.255
exit
From above Configuration you share ... No need to config DHCP excluded address with default gateways in this case your can remove this Configuration in DHCP Configuration..
Router(config)# no ip dhcp excluded-address 192.168.10.1
Router(config)# no ip dhcp excluded-address 192.168.20.1
And Configure
Router(config)# ip default -gateway 192.168.10.1
Router(config)#ip default -gateway 192.168.20.1
And if layer3 switch is used create SVIs and enable ip routing .. if router is used create sub interfàce to inter-Vlan routing between Vlan 10 & Vlan 20