04-04-2013 01:42 AM - edited 03-07-2019 12:37 PM
I am trying to run the 2600 router as a DHCP server for 6 VLANs. I have setup the router and one switch for testing. I have three total switches (all 2950) and two access points (AIR1231G) to setup eventually but would like to make it work on one switch before trying to complicate things further.
If I manually assign an IP address (192.168.2.x) to the PC I can ping every device all the way back to the modem (192.168.7.254) and out to the internet. If I try to get an IP via DHCP I get a private ip (169.254.x.x). DHCP is not working.
I am not sure what step I am missing but I have tried several things and I obviously am missing something. Please help me out with a set of fresh eyes.
My path is as follows:
AT&T DSL MODEM
v
CISCO 2621 ROUTER
v
CISCO CATALYST 2950T SWITCH
v
PC
Modem is connected to FA 0/1 on the router.
Switch (Port FA 0/1) is connected to FA 0/0 on the router.
I have six sub interfaces/VLANs configured on FA 0/0
192.168.1.x - 192.168.6.x
IP designations are as follows
Modem is on 192.168.7.0 network
Router and switch are on 192.168.1.0 network
PC is on VLAN 2 which is on 192.168.2.0 network
Configs Below vvvvvvv
CISCO 2600 Series ROUTER
Building configuration...
Current configuration : 3891 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname JANDJ_ROUTER1
!
enable secret 5 $1$iuCb$Zhp8zsYIS7y/Sb3UQ1lGW/
!
ip subnet-zero
!
!
ip dhcp excluded-address 192.168.1.1 192.168.1.49
ip dhcp excluded-address 192.168.2.1 192.168.2.49
ip dhcp excluded-address 192.168.3.1 192.168.3.49
ip dhcp excluded-address 192.168.4.1 192.168.4.49
ip dhcp excluded-address 192.168.5.1 192.168.5.49
ip dhcp excluded-address 192.168.6.1 192.168.6.49
!
ip dhcp pool 1
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 208.67.222.222
!
ip dhcp pool 2
network 192.168.2.0 255.255.255.0
default-router 192.168.2.1
dns-server 208.67.222.222
!
ip dhcp pool 3
network 192.168.3.0 255.255.255.0
default-router 192.168.3.1
dns-server 208.67.222.222
!
ip dhcp pool 4
network 192.168.4.0 255.255.255.0
default-router 192.168.4.1
dns-server 208.67.222.222
!
ip dhcp pool 5
network 192.168.5.0 255.255.255.0
default-router 192.168.5.1
dns-server 208.67.222.222
!
ip dhcp pool 6
network 192.168.6.0 255.255.255.0
default-router 192.168.6.1
dns-server 208.67.222.222
!
!
!
!
interface FastEthernet0/0
description Connection to JANDJ_HOME1
no ip address
duplex auto
speed auto
!
interface FastEthernet0/0.1
encapsulation dot1Q 1 native
ip address 192.168.1.1 255.255.255.0
ip access-group 1 in
no ip redirects
ip nat inside
!
interface FastEthernet0/0.2
encapsulation dot1Q 2
ip address 192.168.2.1 255.255.255.0
ip access-group 2 in
no ip redirects
ip nat inside
!
interface FastEthernet0/0.3
encapsulation dot1Q 3
ip address 192.168.3.1 255.255.255.0
ip access-group 3 in
no ip redirects
ip nat inside
!
interface FastEthernet0/0.4
encapsulation dot1Q 4
ip address 192.168.4.1 255.255.255.0
ip access-group 4 in
no ip redirects
ip nat inside
!
interface FastEthernet0/0.5
encapsulation dot1Q 5
ip address 192.168.5.1 255.255.255.0
ip access-group 5 in
no ip redirects
ip nat inside
!
interface FastEthernet0/0.6
encapsulation dot1Q 6
ip address 192.168.6.1 255.255.255.0
ip access-group 6 in
no ip redirects
ip nat inside
!
interface Serial0/0
no ip address
shutdown
!
interface FastEthernet0/1
ip address 192.168.7.1 255.255.255.0
ip nat outside
duplex auto
speed auto
!
ip nat inside source list 1 interface FastEthernet0/1 overload
ip nat inside source list 2 interface FastEthernet0/0.2 overload
ip nat inside source list 3 interface FastEthernet0/0.3 overload
ip nat inside source list 4 interface FastEthernet0/0.4 overload
ip nat inside source list 5 interface FastEthernet0/0.5 overload
ip nat inside source list 6 interface FastEthernet0/0.6 overload
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.7.254
ip http server
ip pim bidir-enable
!
access-list 1 permit 192.168.1.0 0.0.0.255
access-list 1 permit 192.168.2.0 0.0.0.255
access-list 1 permit 192.168.3.0 0.0.0.255
access-list 1 permit 192.168.4.0 0.0.0.255
access-list 1 permit 192.168.5.0 0.0.0.255
access-list 1 permit 192.168.6.0 0.0.0.255
access-list 1 permit 192.168.7.0 0.0.0.255
access-list 2 permit 192.168.2.0 0.0.0.255
access-list 2 permit 192.168.1.0 0.0.0.255
access-list 2 permit 192.168.7.0 0.0.0.255
access-list 3 permit 192.168.3.0 0.0.0.255
access-list 3 permit 192.168.1.0 0.0.0.255
access-list 3 permit 192.168.7.0 0.0.0.255
access-list 4 permit 192.168.4.0 0.0.0.255
access-list 4 permit 192.168.1.0 0.0.0.255
access-list 4 permit 192.168.7.0 0.0.0.255
access-list 5 permit 192.168.5.0 0.0.0.255
access-list 5 permit 192.168.1.0 0.0.0.255
access-list 5 permit 192.168.7.0 0.0.0.255
access-list 6 permit 192.168.6.0 0.0.0.255
access-list 6 permit 192.168.1.0 0.0.0.255
access-list 6 permit 192.168.7.0 0.0.0.255
!
line con 0
password 7 0539030834406E1D49174744
login
line aux 0
line vty 0 4
password 7 113B1C02021E2B1854387B72
login
!
end
CISCO CATALYST 2950T SWITCH
Current configuration : 3087 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname SWITCH_HOME_1
!
enable secret 5 $1$51zQ$D/I6MxxoOk3zHeQsYAT400
!
ip subnet-zero
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
00:02:39: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/3, changed state to up
interface FastEthernet0/1
switchport mode trunk
!
interface FastEthernet0/2
switchport mode trunk
!
interface FastEthernet0/3
switchport access vlan 2
switchport mode access
spanning-tree portfast
!
interface FastEthernet0/4
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/5
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/6
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/7
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/8
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/9
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/10
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/11
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/12
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/13
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/14
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/15
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/16
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/17
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/18
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/19
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/20
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/21
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/22
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/23
switchport access vlan 999
switchport mode access
shutdown
!
interface FastEthernet0/24
switchport access vlan 999
switchport mode access
shutdown
!
interface GigabitEthernet0/1
description LINK_TO_OFFICE1
switchport mode trunk
!
interface GigabitEthernet0/2
description LINK_TO_SHOP1
switchport mode trunk
!
interface Vlan1
ip address 192.168.1.3 255.255.255.0
ip helper-address 192.168.1.1
no ip route-cache
!
interface Vlan2
ip address 192.168.2.2 255.255.255.0
no ip route-cache
shutdown
!
ip http server
banner login ^C
W A R N I N G
Authorized users only. Violators will be prosecuted. ^C
!
line con 0
password 7 0036160111572B125F331C18
logging synchronous
login
line vty 0 4
password 7 0036160111572B125F331C18
login
line vty 5 15
password 7 113B1C02021E2B1854387B72
login
!
!
end
Solved! Go to Solution.
04-04-2013 03:01 AM
Hi,
the problem is with your ACLs on the f0/0.x subinterfaces because they are dropping the DHCP Discover messages with a source IP of 0.0.0.0 and also why are you natting on your inside subinterfaces ?
Regards
Alain
Don't forget to rate helpful posts.
04-04-2013 01:55 AM
Hello
Router
conf t
service dhcp
Switch
1) no need for the SVI 2 on the 2950 as the router is performing inter-vlan routing
2) Have you created the L2 vlans on the 2950 switch
conf t
vlan 2,999
exit
3) Is vtp correct so it can be propergated to the other switches.
4) Give the switch a defaut-gateway - 192.168.1.1
res
Paul
Please don't forget to rate any posts that have been helpful.
Thanks.
04-04-2013 03:01 AM
Hi,
the problem is with your ACLs on the f0/0.x subinterfaces because they are dropping the DHCP Discover messages with a source IP of 0.0.0.0 and also why are you natting on your inside subinterfaces ?
Regards
Alain
Don't forget to rate helpful posts.
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