I have a SOHO environment for which I'm using Cisco 891-K9 as the ISP GW. But the nature of Cisco 891 is that it's both a router and a switch with 10 ports.
Will switch ports (both access and trunk ports) be properly forwarding broadcast packets/DHCP requests for VLAN or VLANs or would only trunk ports propagate? Is is the case for 891 where, broadcast packets do not flood within one device?
1st option I have is router on stick:
!
interface FastEthernet8
no ip address
duplex auto
speed auto
!
interface FastEthernet8.2
encapsulation dot1Q 10
ip address 10.2.10.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
no cdp enable
!
interface FastEthernet8.70
encapsulation dot1Q 70
ip address 10.70.0.1 255.255.252.0
ip nat inside
ip virtual-reassembly in
no cdp enable
!
!
ip dhcp pool VLAN70
network 10.70.0.0 255.255.252.0
dns-server 8.8.8.8 8.8.4.4
default-router 10.70.0.1
!
ip dhcp pool VLAN2
network 10.2.10.0 255.255.255.0
dns-server 8.8.8.8 8.8.4.4
default-router 10.2.10.1
!
2nd option via SVI:
!
interface FastEthernet0
switchport mode trunk
no ip address
!
interface Vlan2
ip address 10.2.10.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
!
interface Vlan70
ip address 10.70.0.1 255.255.252.0
ip nat inside
ip virtual-reassembly in
!
!
ip dhcp pool VLAN70
network 10.70.0.0 255.255.252.0
dns-server 8.8.8.8 8.8.4.4
default-router 10.70.0.1
!
ip dhcp pool VLAN2
network 10.2.10.0 255.255.255.0
dns-server 8.8.8.8 8.8.4.4
default-router 10.2.10.1
!
Most routers, as far as I've encountered, can only do sub-interface, but seems 891 is a unique case.