VLAN aggregation

In a typical layer 3 switch , Usually a vlan Corresponding to one vlanif Interface to realize the communication between broadcast domains , But it also leads to ip Waste of address .
This makes vlan Production of polymerization ,vlan Aggregation is to set up a large vlan, We call it supervlan, All of the layers will be accessed vlan All row to this big vlan Inside , Then only give this big vlan One vlanif Address of the interface , Equivalent to all vlan Use one vlanif Interface .

Pictured , Our layer 3 switch has a large vlan100, The following access layer switch is set 3 individual vlan：10 20 30.
Three layers of core sw1 To configure ：

[SW1] vlan batch 10 20 30 100
[SW1] interface GigabitEthernet0/0/1
[SW1-GigabitEthernet0/0/1] port link-type trunk
[SW1-GigabitEthernet0/0/1] port trunk allow-pass vlan 10
[SW1] interface GigabitEthernet0/0/2
[SW1-GigabitEthernet0/0/1] port link-type trunk
[SW1-GigabitEthernet0/0/1] port trunk allow-pass vlan 20
[SW1] interface GigabitEthernet0/0/3
[SW1-GigabitEthernet0/0/1] port link-type trunk
[SW1-GigabitEthernet0/0/1] port trunk allow-pass vlan 30
[SW1] vlan 100	# establish Super-VLAN
[SW1-vlan100] aggregate-vlan
[SW1-vlan100] access-vlan 10 20 30  # take VLAN10,20,30 As VLAN100 Of Sub-VLAN
[SW1] interface vlanif 100
[SW1-vlanif100] ip address 192.168.1.254 24
[SW1-vlanif100] arp-proxy inter-sub-vlan-proxy enable # Can make Sub-VLAN Between the Proxy ARP function 

Access layer sw2、sw3、sw4 To configure ：

[SW2] vlan 10
[SW2] interface GigabitEthernet0/0/1
[SW2-GigabitEthernet0/0/1] port link-type trunk
[SW2-GigabitEthernet0/0/1] port trunk allow-pass vlan 10
[SW2] interface GigabitEthernet0/0/2
[SW2-GigabitEthernet0/0/2] port link-type access
[SW2-GigabitEthernet0/0/2] port default vlan 10
[SW2]interface Eth0/0/1
[SW2-Ethernet0/0/1] port link-type access
[SW2-Ethernet0/0/1]  port default vlan 10
[SW3] vlan 20
[SW3] interface GigabitEthernet0/0/1
[SW3-GigabitEthernet0/0/1] port link-type trunk
[SW3-GigabitEthernet0/0/1] port trunk allow-pass vlan20
[SW3] interface GigabitEthernet0/0/2
[SW3-GigabitEthernet0/0/2] port link-type access
[SW3-GigabitEthernet0/0/2] port default vlan20
[SW4] vlan30
[SW4] interface GigabitEthernet0/0/1
[SW4-GigabitEthernet0/0/1] port link-type trunk
[SW4-GigabitEthernet0/0/1] port trunk allow-pass vlan30
[SW4] interface GigabitEthernet0/0/2
[SW4-GigabitEthernet0/0/2] port link-type access
[SW4-GigabitEthernet0/0/2] port default vlan30

Then configure a core layer 3 switch DHCP：

[sw1]dhcp enable
[sw1]ip pool 1
[sw1-ip-pool-HW-1]network 192.168.1.0 mask 24
[sw1-ip-pool-HW-1]gateway-list 192.168.1.254
[sw1-ip-pool-HW-1]quit
[sw1]interface vlanif 100
[sw1-Vlanif100]dhcp select global 
[sw1-Vlanif100]quit

test ：
PC3：

PC4：

PC3 PING PC4:

Different vlan They can communicate with each other .