SG 300 VLAN Not Pulling DHCP

[adam.weight]

I have a Cisco SG 300 28 port switch that I have set in Layer 3 mode. I set up a second VLAN on it (vlan 4). I also set up the scope for DHCP on a Windows server for both VLAN's. The problem I am having, is that VLAN 4 is not pulling DHCP at all. The DHCP server is connected to port 1 on the switch, and the specifics are as follows:

VLAN 1: 192.168.5.251 subnet 255.255.255.0

VLAN 4: 192.168.55.251 subnet 255.255.255.0

DHCP Server 192.168.5.1

Here is the current config:

***************************************************************************************************************************************************

config-file-header
SP-SW1
v1.2.9.44 / R750_NIK_1_2_584_002
CLI v1.0
file SSD indicator excluded
@
vlan database
vlan 4
exit
voice vlan oui-table add 0001e3 Siemens_AG_phone________
voice vlan oui-table add 00036b Cisco_phone_____________
voice vlan oui-table add 00096e Avaya___________________
voice vlan oui-table add 000fe2 H3C_Aolynk______________
voice vlan oui-table add 0060b9 Philips_and_NEC_AG_phone
voice vlan oui-table add 00d01e Pingtel_phone___________
voice vlan oui-table add 00e075 Polycom/Veritel_phone___
voice vlan oui-table add 00e0bb 3Com_phone______________
ip dhcp snooping
ip dhcp snooping information option allowed-untrusted
ip dhcp relay address 192.168.5.1
ip dhcp relay enable
ip dhcp information option
bonjour mode include
bonjour interface range vlan 1
hostname SP-SW1
username cisco password encrypted d2af3f31b3af51945646942749ee1ce9019a73dc privilege 15
ip name-server  192.168.5.1
ip telnet server
!
interface vlan 1
  ip address 192.168.5.251 255.255.255.0
  no ip address dhcp
  ip dhcp relay enable
!
interface vlan 4
  name Guest
  ip address 192.168.55.251 255.255.255.0
  ip dhcp relay enable
!
interface gigabitethernet1
  description SPDC1
  ip dhcp snooping trust
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet2
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet3
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet4
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet5
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet6
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet7
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet8
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet9
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet10
  spanning-tree portfast
  switchport mode access
  switchport access vlan 4
!
interface gigabitethernet11
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet12
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet13
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet14
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet15
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet16
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet17
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet18
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet19
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet20
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet21
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet22
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet23
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet24
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet25
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet26
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet27
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet28
  switchport trunk allowed vlan add 4
!
ip helper-address all 192.168.5.1 37 42 49 53 137 138

*********************************************************************************************************************************************

I have the ip helper-address set to all because I couldn't get it to take any other command. I tried attaching the ip helper-address just to the vlan 4 interface but received the following error:

SP-SW1#conf t

SP-SW1(config)#int vlan 4

SP-SW1(config-if)#ip helper-address 192.168.5.1

% missing mandatory parameter

SP-SW1(config-if)#

[useridcisco1]

hello,
disable dhcp snopping and verify is dhcp relay is working properly


Sent from Cisco Technical Support Android App

[adam.weight]

Thanks for the info. I just tried disabling IP Snooping and it still does not work. When I attach a computer to port 10 (vlan4) I get no dhcp address. Here is the updated config:

*************************************************************************************************************

config-file-header
SP-SW1
v1.2.9.44 / R750_NIK_1_2_584_002
CLI v1.0
file SSD indicator excluded
@
vlan database
vlan 4
exit
voice vlan oui-table add 0001e3 Siemens_AG_phone________
voice vlan oui-table add 00036b Cisco_phone_____________
voice vlan oui-table add 00096e Avaya___________________
voice vlan oui-table add 000fe2 H3C_Aolynk______________
voice vlan oui-table add 0060b9 Philips_and_NEC_AG_phone
voice vlan oui-table add 00d01e Pingtel_phone___________
voice vlan oui-table add 00e075 Polycom/Veritel_phone___
voice vlan oui-table add 00e0bb 3Com_phone______________
ip dhcp relay address 192.168.5.1
ip dhcp relay enable
ip dhcp information option
bonjour mode include
bonjour interface range vlan 1
hostname SP-SW1
username cisco password encrypted d2af3f31b3af51945646942749ee1ce9019a73dc privilege 15
ip name-server  192.168.5.1
ip telnet server
!
interface vlan 1
  ip address 192.168.5.251 255.255.255.0
  no ip address dhcp
  ip dhcp relay enable
!
interface vlan 4
  name Guest
  ip address 192.168.55.251 255.255.255.0
  ip dhcp relay enable
!
interface gigabitethernet1
  description SPDC1
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet2
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet3
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet4
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet5
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet6
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet7
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet8
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet9
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet10
  spanning-tree portfast
  switchport mode access
  switchport access vlan 4
!
interface gigabitethernet11
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet12
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet13
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet14
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet15
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet16
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet17
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet18
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet19
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet20
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet21
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet22
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet23
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet24
  spanning-tree portfast
  switchport mode access
!
interface gigabitethernet25
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet26
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet27
  spanning-tree guard root
  switchport trunk allowed vlan add 4
!
interface gigabitethernet28
  switchport trunk allowed vlan add 4
!
ip helper-address all 192.168.5.1 37 42 49 53 137 138

***********************************************************************************************

[paul driver · Accepted solution]

Hello

Is the dhcp scope in the windows server authorised and active?

I cannot see ip routing enable on this switch?

res

Paul

Please don't forget to rate any posts that have been helpful.

Thanks.

[adam.weight]

Thank you, adding an IP route fixed it. I hadn't added the Internet route yet because I was trying to get it configured before adding it to the network, and it wouldn't let me add the route to 0.0.0.0 without the firewall connected.

The reason you did not see IP Routing enabled yet is because I was planning on putting this as the default gateway for all devices, but could not at the time because the firewall was not plugged into it yet. (Couldn't make that change while users were accessing the network), and without the firewall plugged in it was giving me an error when I tried to input the route to 0.0.0.0.

I plugged the firewall into this device and then added the following

ip route 0.0.0.0 0.0.0.0 192.168.5.254

Once I added that route, the DHCP started working on VLAN 4.

Thanks again.

[router Vlan dhcp]

Why did you use 192.168.5.254 in ip route command? i cant see any other reference of this ip above

[jawad-mukhtar]

Try giving command

ip-helper address (DHCP Server IP under Vlan)

Do Rate All Helpful Posts

[adam.weight]

I had already tried that and I received an error. The only option I was given on this switch was to do the ip helper-address x.x.x.x all parameter. See error below:

SP-SW1#conf t

SP-SW1(config)#int vlan 4

SP-SW1(config-if)#ip helper-address 192.168.5.1

% missing mandatory parameter

SP-SW1(config-if)#