08-14-2006 05:15 PM - edited 03-03-2019 04:30 AM
Hi All,
I have a issue with dhcp clients communicating with DHCP server on windowds 2003.
Layer 3 switch is configured with IP helper to forward request to DHCP server on 152.153.238.0 /24 subnet users can get IP address from dhcp server when they are in particulae vlan but when a user moves from one vlan to other user is not getting IP address from dhcp server,Can anyone help me out here....
Solved! Go to Solution.
08-17-2006 07:27 AM
I have heard of similar issues when using superscopes. Try breaking your superscope into seperate scopes.
08-14-2006 05:21 PM
Could you post your config ?
Have you configured a helper address on all of these VLAN interfaces ?
Paresh
08-14-2006 05:31 PM
Paresh ,
below is config..
sh runn
Building configuration...
Current configuration : 4169 bytes
!
! Last configuration change at 18:43:31 Msia Fri Aug 11 2006
! NVRAM config last updated at 18:40:33 Msia Fri Aug 11 2006
!
version 12.2
no service pad
service timestamps debug datetime msec localtime
service timestamps log datetime msec localtime
service password-encryption
!
hostname CORE1
!
logging buffered 20000 debugging
enable secret 5 $1$jofs$LDlLcqesLUYfOz9QOBMhP1
!
no aaa new-model
clock timezone Msia 8
switch 1 provision ws-c3750g-12s
ip subnet-zero
ip routing
!
ip dhcp-server 152.153.238.33
!
!
!
errdisable recovery cause udld
errdisable recovery cause bpduguard
errdisable recovery cause security-violation
errdisable recovery cause channel-misconfig
errdisable recovery cause pagp-flap
errdisable recovery cause dtp-flap
errdisable recovery cause link-flap
errdisable recovery cause gbic-invalid
errdisable recovery cause psecure-violation
errdisable recovery cause dhcp-rate-limit
errdisable recovery cause unicast-flood
errdisable recovery cause vmps
errdisable recovery cause loopback
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
interface GigabitEthernet1/0/1
description ##### Conn to Server Room | Module S/N: AGS1018L2W4 #####
no switchport
ip address 10.89.65.26 255.255.255.252
ip helper-address 152.153.238.33
!
interface GigabitEthernet1/0/2
description #### Conn to BSM_COMMSW01 Port Gig0/1 ####
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet1/0/3
description ##### Conn to EER Paint | Module S/N: FNS1019C1WQ #####
switchport access vlan 2
switchport mode access
!
interface GigabitEthernet1/0/4
description ##### Conn to Store | Module S/N: AGS102005UC #####
switchport access vlan 2
switchport mode access
!
interface GigabitEthernet1/0/5
description ##### Conn to Maintenance | Module S/N: AGS102005UQ #####
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet1/0/6
description ##### Conn to Logistics | Module S/N: AGS102005SM #####
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet1/0/7
description ##### Conn to IS | Module S/N: AGS102005TJ #####
switchport access vlan 2
switchport mode access
!
interface GigabitEthernet1/0/8
description ##### Conn to EER ZAL | Module S/N: FNS1019R0P8 #####
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface GigabitEthernet1/0/9
!
interface GigabitEthernet1/0/10
!
interface GigabitEthernet1/0/11
!
interface GigabitEthernet1/0/12
!
interface Vlan1
no ip address
shutdown
!
interface Vlan2
ip address 10.89.72.3 255.255.255.0
ip helper-address 152.153.238.33
!
interface Vlan3
ip address 10.89.73.11 255.255.255.0
!
interface Vlan4
ip address 10.89.74.11 255.255.255.0
!
ip default-gateway 10.89.65.25
ip classless
ip route 0.0.0.0 0.0.0.0 10.89.65.25
ip http server
!
arp 10.89.72.86 00e0.db06.89d7 ARPA
snmp-server community public RO
!
control-plane
!
banner motd ^CCC
!
line con 0
password 7 121A0C041104
logging synchronous
login
line vty 0 4
password 7 045802150C2E
no login
line vty 5 15
no login
!
ntp clock-period 36028692
ntp server 152.153.238.41
!
end
08-14-2006 05:50 PM
Hi,
Can you try the following:
interface Vlan3
ip helper-address 152.153.238.33
!
interface Vlan4
ip helper-address 152.153.238.33
!
That should fix it.
Pls do rate posts that help...
Paresh
08-14-2006 06:08 PM
do i have to remove gateway((interface Vlan3
ip address 10.89.73.11 255.255.255.0
!
interface Vlan4
ip address 10.89.74.11 255.255.255.0))
for that particular subnet and just place Ip helper-address for interface vlan3 & vlan4
08-14-2006 06:13 PM
NO, don't remove the addresses !!
Just add the config I supplied to what's already there...
PK
08-14-2006 06:16 PM
Sori to say but still same its not working........
Do i have to configure Dhcp relay agent or some thing like that
08-14-2006 06:46 PM
Have you configured appropriate scopes on your DHCP server for these subnets ?
08-14-2006 06:53 PM
Can you ensure the DHCP server is reachable from other than its original subnet ?
e.g. access from VLAN 2, 3, 4 VLAN subnet ?
Any default gateway in DHCP server ?
Please provide the trace route result from switch to DHCP server. Thx.
08-14-2006 06:58 PM
I have created superscope in dhcp server and added this subnets under that ,Problem i have here is users can get ip in all vlans but when a user move from vlan 2 to vlans 3 he is not able to get ip address from dhcp server & at same time i am getting error like DHCP server is not reachable....
08-14-2006 07:03 PM
Can you provide the trace route from a PC at VLAN 3 to the DHCP server ?
If add the ip-helper address at VLAN 3, it should work.
08-14-2006 07:04 PM
Are you doing a DHCP release on the user after you move them across to the new VLAN ?
08-14-2006 07:37 PM
Yep say when i am in vlan3 and move to vlan2 i relese ip address but when i renew i dont get IP address and after a while still still its getting ol ip addrees of vlan3 when i tracert it not reaching local gateway.
08-14-2006 07:44 PM
Sorry for state it clearly. What I mean use a PC w/ static or valid IP in VLAN 3 to trace route to the DHCP server. And also trace from DHCP server to the switch VLAN 3 interface. Please try it ans advise the result.
08-14-2006 10:16 PM
C:\Documents and Settings\sosrin>tracert 152.153.238.33
Tracing route to 152.153.238.33 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms 10.89.72.3
2 <1 ms <1 ms <1 ms 10.89.65.25
3 <1 ms <1 ms <1 ms 152.153.238.33
Trace complete.
C:\Documents and Settings\sosrin>
and 10.89.65.25 is configured on this switch
sh runn
Building configuration...
Current configuration : 3827 bytes
!
version 12.2
no service pad
service timestamps debug uptime
service timestamps log datetime
no service password-encryption
service sequence-numbers
!
hostname C3750G
!
enable secret xxx
enable password
!
switch 1 provision ws-c3750g-24t
ip subnet-zero
ip routing
no ip dhcp relay information check
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
!
interface GigabitEthernet1/0/19
description RJ45 to ATI Rapier L3
no switchport
ip address 10.89.65.25 255.255.255.252
ip helper-address 152.153.238.33
!
interface GigabitEthernet1/0/20
switchport access vlan 238
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet1/0/21
switchport access vlan 238
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet1/0/22
switchport access vlan 238
switchport mode access
speed 1000
duplex full
spanning-tree portfast
!
interface GigabitEthernet1/0/23
description RJ45 to Peribit appliance
no switchport
ip address 10.89.65.17 255.255.255.248
speed 100
duplex full
!
interface GigabitEthernet1/0/24
description Trunk connection CAT3550 int G0/1
switchport trunk encapsulation dot1q
switchport mode trunk
!
interface Vlan1
no ip address
!
interface Vlan238
ip address 152.153.238.3 255.255.255.0
!
interface Vlan240
ip address 10.89.75.11 255.255.255.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.89.65.19
ip route 1.1.1.0 255.255.255.0 10.89.65.26
ip route 10.89.72.0 255.255.255.0 10.89.65.26
ip route 10.89.73.0 255.255.255.0 10.89.65.26
ip route 10.89.74.0 255.255.255.0 10.89.65.26
ip http server
!
!
logging trap debugging
snmp-server community n5 RO
snmp-server enable traps tty
!
control-plane
!
!
line con 0
line vty 0 4
password
login
line vty 5 15
no login
!
end
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