1. 192.168. 192.168.33.1 Vlan 34 Solution 1: [1] change vlan 33 attached to SG500 to new vlan (vlan 34) [2] SG500 as DHCP server for vlan 34 [3] DHCP ACL filter for vlan 33 on SG500 DHCP filter For vlan 33 ip access-l ext DHCP deny udp an bootpc an bootps int vlan 33 service input DHCP default-action permit-any //filter out the DHCP request from client to this vlan, allow other packets Solution 1: Use New Vlan

2. Vlan 33 SG500 Vlan 50 L2 switch DHCP filter For vlan 33 Solution 2: [1] add a L2 switch between router & SG500 [2] use ACL to filter DHCP for vlan 33 in SG500 [3] migrate all vlan 33 from SG500 to the new L2 switch router Solution 2: Add L2 Switch

3. Router 192.168.33.1 MAC: 0000.0000.0001 GW: SG500 Solution 3: [1] both router and SG500 as DHCP server for vlan 33 [2] SG500 use DHCP host pool for vlan 33 to prevent any allocation Ip dhcp server Ip dhcp pool host 33 Add 192.168.33.1 /24 hardware 0000.0000.0001 // MAC of router //this add will never be assigned since it’s already used by router DHCP Server For vlan 33 192.168.33.2 Solution 3: Dual DHCP Server

4. Router 192.168.33.1 DHCP pool for vlan 33 GW: SG500 Routing table: 0.0.0.0/0 12.100.100.78 192.168.33.0/24 192.168.33.1 192.168.50.0/24 192.168.33.2 PC2-> Internet ? Suboptimal PC2-> Router(L2)-> SG500(L3)->Router(L2)->Router(L3)->Internet PC2 PC1 ✓ PC2 Router(L2)->SG500(L2) PC1 PC2-> PC5 ✓ PC2-> Router(L2)->SG500(L3)->PC5 PC1/PC5 -> Internet ✓ PC1/PC5 -> SG500(L3)->Router(L2)->Router(L3)->Internet PC1 PC5 ✓ PC1 SG500(L3) PC5 SG 500 192.168.33.2 vlan 33 192.168.50.2 vlan 50 Routing Table: 0.0.0.0/0 192.168.33.1 192.168.33.0/24 192.168.33.2 192.168.50.0/24 192.168.50.2 PC2 192.168.33.200 GW: SG 500 ? Internet PC1 192.168.33.100 GW: SG 500 ✓ Suboptimal Route – SG 500 as Default Gateway Router 0.0.0.0/0 12.100.100.78 PC5 192.168.50.100 GW: SG 500 ✓ Solution Migrate PC2 from Router to SG500

5. Router 192.168.33.1 DHCP pool for vlan 33 GW: self Routing table: 0.0.0.0/0 12.100.100.78 192.168.33.0/24 192.168.33.1 192.168.50.0/24 192.168.33.2 PC2-> Internet ✓ PC2-> Router(L3)-> Internet PC2-> PC5 ? Suboptimal PC2-> Router(L3)->Router(L2)->SG500(L3)->PC5 PC1-> Internet ✓ PC1-> SG500(L2)->Router(L3)->Internet PC1-> PC5 ? Suboptimal PC1-> SG500(L2)->Router(L3)->SG500(L3)->PC5 PC5-> PC1 ✓ PC5-> SG500(L3)->PC1 PC5-> Internet ✓ PC5-> SG500(L3) ->Router(L2)->Router(L3)->Internet SG 500 192.168.33.2 vlan 33 192.168.50.2 vlan 50 Routing Table: 0.0.0.0/0 192.168.33.1 192.168.50.0/24 192.168.50.2 192.168.33.0/24 192.168.33.2 PC2 192.168.33.200 GW: Router ? Internet PC1 192.168.33.100 GW: Router ? Suboptimal Route –Router as Default Gateway Router 0.0.0.0/0 12.100.100.78 PC5 192.168.50.100 GW: SG 500 ✓ Solution SG500 as GW PC2 -> SG500