DHCP – DHCP Request Failed, APIPA Being Used

ciscodhcppacket-tracerrouting

So, I have the following network configuration in Packet Tracer.Network configuration

The router is configured with DHCP. The ports on the switches are configured with access mode – for those that belong to the PCs. The unused ports are shut down. The ports between the switches and the ports between the switch and the router are configured as trunk ports. All the PCs that are connected to the S1 that is directly connected to the R1 get the IP addresses from the router. However, the PCs that are connected to the S2 and S3 don't – instead they get the message "DHCP request failed, APIPA being used". What could be the problem?

Here is the link for the configurations – https://1drv.ms/u/s!AiRtffZ-QpFphY8iof_YGdcuua3KXw

The configurations for R1:

ip dhcp pool Head  
 network 10.10.10.0 255.255.255.0  
 default-router 10.10.10.1  
ip dhcp pool R&D  
 network 10.10.20.0 255.255.255.0  
 default-router 10.10.20.1  
ip dhcp pool M&S  
 network 10.10.30.0 255.255.255.0  
 default-router 10.10.30.1  
ip dhcp pool Lab  
 network 10.10.40.0 255.255.255.0  
 default-router 10.10.40.1  
ip dhcp pool WS  
 network 10.10.50.0 255.255.255.0  
 default-router 10.10.50.1  

no ip cef  
no ipv6 cef  

spanning-tree mode pvst  

interface FastEthernet0/0  
 no ip address  
 ip nat inside  
 duplex auto  
 speed auto  
!  
interface FastEthernet0/0.1  
 encapsulation dot1Q 1 native  
 ip address 10.10.1.1 255.255.255.0  
!  
interface FastEthernet0/0.10  
 encapsulation dot1Q 10  
 ip address 10.10.10.1 255.255.255.0  
!  
interface FastEthernet0/0.20  
 encapsulation dot1Q 20  
 ip address 10.10.20.1 255.255.255.0  
!  
interface FastEthernet0/0.30  
 encapsulation dot1Q 30  
 ip address 10.10.30.1 255.255.255.0  
!  
interface FastEthernet0/0.40  
 encapsulation dot1Q 40  
 ip address 10.10.40.1 255.255.255.0  
!  
interface FastEthernet0/0.50  
 encapsulation dot1Q 50  
 ip address 10.10.50.1 255.255.255.0  
!  
interface FastEthernet0/0.99  
 encapsulation dot1Q 99  
 ip address 10.10.99.1 255.255.255.0  
!  
interface FastEthernet0/1  
 ip address 85.143.163.237 255.255.255.0  
 ip nat outside  
 duplex auto  
 speed auto  

interface Vlan1  
 no ip address  
 shutdown  

ip nat inside source list 1 interface FastEthernet0/1 overload  
ip classless  

ip flow-export version 9  

access-list 1 permit 10.10.0.0 0.0.255.255  

line con 0  

line aux 0  

line vty 0 4  
 login  

The configuration for S1:

spanning-tree mode pvst  
!  
interface FastEthernet0/1   
 switchport mode trunk  
!  
interface FastEthernet0/2  
 switchport mode trunk  
!  
interface FastEthernet0/3  
 shutdown  
!  
interface FastEthernet0/4  
 switchport mode trunk  
!  
interface FastEthernet0/5  
 shutdown  
!  
interface FastEthernet0/6  
 shutdown  
!  
interface FastEthernet0/7  
 shutdown   
!  
interface FastEthernet0/8  
 shutdown  
!  
interface FastEthernet0/9  
 shutdown  
!  
interface FastEthernet0/10  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/11   
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/12  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/13  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/14  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/15  
 switchport access vlan 10  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/16  
 switchport access vlan 10  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/17  
 switchport access vlan 30  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/18  
 switchport access vlan 30  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/19  
 switchport access vlan 30  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/20  
 switchport access vlan 30  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/21  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/22  
 switchport access vlan 20  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/23  
 switchport access vlan 30  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/24  
 shutdown  
!  
interface Vlan1  
 no ip address  
 shutdown  
!  
interface Vlan99  
 ip address 10.10.99.10 255.255.255.0  
!  
ip default-gateway 10.10.99.1  

line con 0  
!  
line vty 0 4  
 login  
line vty 5 15  
 login  
!  

The configurations for S2:

spanning-tree mode pvst  
!  
interface FastEthernet0/1  
 shutdown  
!  
interface FastEthernet0/2  
 switchport mode trunk  
!  
interface FastEthernet0/3  
 switchport mode trunk  
!  
interface FastEthernet0/4  
 shutdown  
!  
interface FastEthernet0/5  
 shutdown  
!  
interface FastEthernet0/6  
 shutdown  
!  
interface FastEthernet0/7  
 shutdown  
!  
interface FastEthernet0/8  
 shutdown  
!  
interface FastEthernet0/9  
 shutdown  
!  
interface FastEthernet0/10  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/11  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/12  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/13  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/14  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/15  
 switchport access vlan 40  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/16  
 shutdown  
!  
interface FastEthernet0/17  
 shutdown  
!  
interface FastEthernet0/18   
 shutdown  
!  
interface FastEthernet0/19  
 shutdown  
!  
interface FastEthernet0/20  
 shutdown  
!  
interface FastEthernet0/21  
 shutdown  
!  
interface FastEthernet0/22  
 shutdown  
!  
interface FastEthernet0/23  
 shutdown  
!  
interface FastEthernet0/24  
 shutdown  
!  
interface Vlan1  
 no ip address  
 shutdown  
!  
interface Vlan99  
 ip address 10.10.99.20 255.255.255.0  
!  
ip default-gateway 10.10.99.1  

line con 0  
!  
line vty 0 4  
 login  
line vty 5 15  
 login  
!  

The configurations for S3:

spanning-tree mode pvst  
!  
interface FastEthernet0/1  
 shutdown  
!  
interface FastEthernet0/2  
 shutdown  
!  
interface FastEthernet0/3  
!  
interface FastEthernet0/4  
!  
interface FastEthernet0/5  
 shutdown  
!  
interface FastEthernet0/6  
 shutdown  
!  
interface FastEthernet0/7  
 shutdown  
!  
interface FastEthernet0/8  
 shutdown  
!  
interface FastEthernet0/9  
 shutdown  
!  
interface FastEthernet0/10  
 switchport access vlan 50  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/11  
 switchport access vlan 50  
 switchport mode access  
 spanning-tree portfast  
!  
interface FastEthernet0/12  
 shutdown  
!  
interface FastEthernet0/13  
 shutdown  
!  
interface FastEthernet0/14  
 shutdown  
!  
interface FastEthernet0/15  
 shutdown  
!  
interface FastEthernet0/16  
 shutdown  
!  
interface FastEthernet0/17  
 shutdown  
!  
interface FastEthernet0/18  
 shutdown  
!  
interface FastEthernet0/19  
 shutdown  
!  
interface FastEthernet0/20   
 shutdown  
!  
interface FastEthernet0/21  
 shutdown  
!  
interface FastEthernet0/22  
 shutdown  
!  
interface FastEthernet0/23  
 shutdown  
!  
interface FastEthernet0/24  
 shutdown  
!  
interface Vlan1  
 no ip address  
 shutdown  
!  
interface Vlan99  
 ip address 10.10.99.30 255.255.255.0  
!  
ip default-gateway 10.10.99.1  

line con 0  
!  
line vty 0 4  
 login  
line vty 5 15  
 login  
!  

Best Answer

Why didn't you configure trunks on S3?

It's a very good idea to use the description command on the interfaces to describe where the interface connects. It's not labeled on the drawing, and we are left to guess. For instance, S1 has trunks on F0/1, F0/2, and F0/4, but which connects to S2, and on which S2 interface does it connect? It's a good idea to use the show cdp neighbor command to double-check that what you label matches the actual connection.

You should also create the VLANs on each switch, and set S1 as the root switch for the VLANs.

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