I've set up DHCP pools on a layer 3 switch that goes out to 13 layer 2 switches. Most of which have their own subnet and VLANs, and everything works fine when that's the case. But when there are two VLANs/subnets sharing a switch, the hosts on that VLAN or subnet can't seem to get their IP address assigned by the DHCP server, and instead have link-local addresses. What am I probably doing wrong?
I'm using Cisco Catalyst switches. I've also been trying to figure it out with Packet Tracer, but no having much luck.
Here are the details of the vlans and subnets:
Below are some of the configs. Including the main L3 switch, and some of the switches that are having problems.
Multilayer Switch
L3CORE#show run
Building configuration...
Current configuration : 5687 bytes
!
version 12.2(37)SE1
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname L3CORE
!
!
!
ip dhcp excluded-address 10.0.0.1
ip dhcp excluded-address 10.0.2.1
ip dhcp excluded-address 10.0.2.65
ip dhcp excluded-address 10.0.2.129
ip dhcp excluded-address 10.0.2.161
ip dhcp excluded-address 10.0.2.193
ip dhcp excluded-address 10.0.2.225
ip dhcp excluded-address 10.0.3.1
ip dhcp excluded-address 10.0.3.33
ip dhcp excluded-address 10.0.3.65
ip dhcp excluded-address 10.0.3.81
ip dhcp excluded-address 10.0.3.97
ip dhcp excluded-address 10.0.3.113
ip dhcp excluded-address 10.0.3.121
!
ip dhcp pool 425
network 10.0.0.0 255.255.254.0
ip dhcp pool 325
network 10.0.2.0 255.255.255.192
default-router 10.0.0.1
ip dhcp pool 350
network 10.0.3.80 255.255.255.240
default-router 10.0.0.1
ip dhcp pool vlan350
network 10.0.3.80 255.255.255.240
default-router 10.0.3.81
ip dhcp pool 150
network 10.0.2.192 255.255.255.224
default-router 10.0.0.1
ip dhcp pool range
ip dhcp pool vlan425
network 10.0.0.0 255.255.254.0
ip dhcp pool vlan325
network 10.0.2.0 255.255.255.192
default-router 10.0.2.1
ip dhcp pool vlan225
network 10.0.2.64 255.255.255.192
default-router 10.0.2.65
ip dhcp pool vlan375
network 10.0.2.128 255.255.255.224
default-router 10.0.2.129
ip dhcp pool vlan300
network 10.0.2.160 255.255.255.224
default-router 10.0.2.161
ip dhcp pool vlan150
network 10.0.2.192 255.255.255.224
default-router 10.0.2.193
ip dhcp pool vlan250
network 10.0.2.224 255.255.255.224
default-router 10.0.2.225
ip dhcp pool vlan275
network 10.0.3.0 255.255.255.224
default-router 10.0.3.1
ip dhcp pool vlan125
network 10.0.3.32 255.255.255.224
default-router 10.0.3.33
ip dhcp pool vlan200
network 10.0.3.64 255.255.255.240
default-router 10.0.3.65
ip dhcp pool vlan175
network 10.0.3.96 255.255.255.240
default-router 10.0.3.97
ip dhcp pool vlan400
network 10.0.3.120 255.255.255.252
default-router 10.0.3.121
ip dhcp pool vlan100
network 10.0.3.112 255.255.255.248
default-router 10.0.3.113
!
!
ip routing
!
!
!
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface FastEthernet0/1
switchport trunk allowed vlan 100,350,375,400,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/2
switchport trunk allowed vlan 325,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/3
switchport trunk allowed vlan 225,275,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/4
switchport trunk allowed vlan 150,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/5
switchport trunk allowed vlan 175,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/6
switchport trunk allowed vlan 250,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/7
switchport trunk allowed vlan 425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/8
switchport trunk allowed vlan 375,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/9
switchport trunk allowed vlan 425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/10
switchport trunk allowed vlan 425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/11
switchport trunk allowed vlan 325,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/12
switchport trunk allowed vlan 300,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/13
switchport trunk allowed vlan 200,425
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/14
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface Vlan1
no ip address
shutdown
!
interface Vlan100
mac-address 00e0.8f6d.4301
ip address 10.0.3.113 255.255.255.248
!
interface Vlan125
mac-address 00e0.8f6d.4302
ip address 10.0.3.33 255.255.255.224
!
interface Vlan150
mac-address 00e0.8f6d.4303
ip address 10.0.2.193 255.255.255.224
!
interface Vlan175
mac-address 00e0.8f6d.4304
ip address 10.0.3.97 255.255.255.240
!
interface Vlan200
mac-address 00e0.8f6d.4305
ip address 10.0.3.65 255.255.255.240
!
interface Vlan225
mac-address 00e0.8f6d.4306
ip address 10.0.2.65 255.255.255.192
!
interface Vlan250
mac-address 00e0.8f6d.4307
ip address 10.0.2.225 255.255.255.224
!
interface Vlan275
mac-address 00e0.8f6d.4308
ip address 10.0.3.1 255.255.255.224
!
interface Vlan300
mac-address 00e0.8f6d.4309
ip address 10.0.2.161 255.255.255.224
!
interface Vlan325
mac-address 00e0.8f6d.430a
ip address 10.0.2.1 255.255.255.192
!
interface Vlan350
mac-address 00e0.8f6d.430b
ip address 10.0.3.81 255.255.255.240
!
interface Vlan375
mac-address 00e0.8f6d.430c
ip address 10.0.2.129 255.255.255.224
!
interface Vlan400
mac-address 00e0.8f6d.430d
ip address 10.0.3.121 255.255.255.252
!
interface Vlan425
mac-address 00e0.8f6d.430e
ip address 10.0.0.1 255.255.254.0
!
router rip
network 10.0.0.0
!
ip classless
!
ip flow-export version 9
!
!
!
!
!
!
!
!
line con 0
!
line aux 0
!
line vty 0 4
login
!
!
!
!
end
Switch 03
S03#show run
Building configuration...
Current configuration : 2485 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname S03
!
!
!
clock timezone awst 8
!
no ip domain-lookup
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/3
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/4
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/5
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/6
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/7
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/8
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/9
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/10
switchport access vlan 275
switchport mode access
!
interface FastEthernet0/11
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/12
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/13
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/14
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/15
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/16
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/17
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/18
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/19
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/20
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/21
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/22
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/23
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/24
switchport access vlan 225
switchport mode access
!
interface GigabitEthernet0/1
switchport trunk allowed vlan 225,275,425
switchport mode trunk
!
interface GigabitEthernet0/2
switchport access vlan 425
switchport mode access
!
interface Vlan1
no ip address
shutdown
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
!
end
Switch 07
S07#show run
Building configuration...
Current configuration : 2511 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname S07
!
!
!
clock timezone awst 8
!
no ip domain-lookup
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/3
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/4
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/5
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/6
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/7
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/8
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/9
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/10
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/11
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/12
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/13
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/14
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/15
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/16
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/17
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/18
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/19
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/20
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/21
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/22
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/23
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/24
switchport access vlan 225
switchport mode access
!
interface GigabitEthernet0/1
switchport trunk allowed vlan 225,425
switchport mode trunk
!
interface GigabitEthernet0/2
switchport access vlan 425
switchport mode access
!
interface Vlan1
no ip address
shutdown
!
ip default-gateway 10.0.0.1
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
!
end
Switch 08
S08#show run
Building configuration...
Current configuration : 2582 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname S08
!
!
ip dhcp excluded-address 10.0.2.65
!
clock timezone awst 8
!
no ip domain-lookup
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/3
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/4
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/5
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/6
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/7
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/8
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/9
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/10
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/11
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/12
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/13
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/14
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/15
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/16
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/17
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/18
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/19
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/20
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/21
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/22
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/23
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/24
switchport access vlan 225
switchport mode access
!
interface GigabitEthernet0/1
switchport trunk allowed vlan 225,425
switchport mode trunk
!
interface GigabitEthernet0/2
switchport access vlan 425
switchport mode access
!
interface Vlan1
no ip address
shutdown
!
interface Vlan225
mac-address 0007.ec6d.3c01
no ip address
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
!
end
Switch 09
S09#show run
Building configuration...
Current configuration : 2481 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname S09
!
!
!
clock timezone awst 8
!
no ip domain-lookup
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/2
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/3
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/4
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/5
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/6
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/7
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/8
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/9
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/10
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/11
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/12
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/13
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/14
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/15
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/16
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/17
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/18
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/19
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/20
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/21
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/22
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/23
switchport access vlan 225
switchport mode access
!
interface FastEthernet0/24
switchport access vlan 225
switchport mode access
!
interface GigabitEthernet0/1
switchport trunk allowed vlan 225,425
switchport mode trunk
!
interface GigabitEthernet0/2
switchport access vlan 425
switchport mode access
!
interface Vlan1
no ip address
shutdown
!
!
!
!
line con 0
!
line vty 0 4
login
line vty 5 15
login
!
!
!
!
end
Best Answer
I think one big problem is that you have not defined the VLANs on the access switches. Yes, you have the SVIs for the VLANs, but you didn't globally define the VLANs.
For example:
Forgetting to do that will often cause problems like you describe. Add that to all the DHCP server problems you have on the layer-3 switch, and you have a real mess.
See this question for the same problem, and the answer was to define the VLANs.