Cisco 3750 refuses to issue DHCP for VLAN

It should work as it is configured with host directly attached to port Gi1/0/27 if port successfully negotiate speed.
Since it is not working, points of failure can be that switch VTP mode is client and that assigning port to VLAN 207 did not create VLAN207. Also SVI for VLAN 207 can be shutdown or in up down state. Please check if VLAN 207 exists on switch and that when host is connected to port Gi1/0/27 status of SVI 207 and port is up up.
sh vlan brief | i 207
sh ip int brief | i Vlan207|1/0/27

Thanks for the quick reply,

Glad I haven't made a stupid mistake that my eyes failed to see. I

Vlan is up

207  GuestWifiUser                    active    Gi1/0/27, Gi1/0/28, Gi1/0/45

Vlan207                192.168.70.254  YES NVRAM  up                    up

Regards

When you manually assign IP address to host can you ping default gateway and some other addresses?

Yes if I assign a static ip within the VLAN207 subnet I can ping the SVI address. I even did it without a gateway interface in the IP config to ensure it wasn't being routed somehow!

Regards

In that case In that case I expect that there is some IOS Bug present there is at least several of DHCP IOS bugs related to 3750 switches. I don't see other explanation. What I would try is to create loopback interface and create ip helper under SVI 207 pointing to switch loopback (desperate times call for desperate measures). Sure, IOS upgrade is also an option.

Ok I'll give it a try. Are u suggesting a loop back address within the same subnet? Like 192.168.70.253?

You can't use IP address from the same subnet it would be overlapping network - not allowed... :)

Still no good!

*Mar  6 16:01:20.054:   DHCPD: htype 1 chaddr 00e0.ed12.2168
*Mar  6 16:01:20.054:   DHCPD: giaddr = 192.168.70.254
*Mar  6 16:01:20.054:   DHCPD: interface = Loopback1
*Mar  6 16:01:20.054:   DHCPD: class id 4d53465420352e30
*Mar  6 16:01:24.055: DHCPD: Sending notification of DISCOVER:
*Mar  6 16:01:24.055:   DHCPD: htype 1 chaddr 00e0.ed12.2168
*Mar  6 16:01:24.055:   DHCPD: interface = Vlan207
*Mar  6 16:01:24.055:   DHCPD: class id 4d53465420352e30
*Mar  6 16:01:24.055: DHCPD: Sending notification of DISCOVER:
*Mar  6 16:01:24.055:   DHCPD: htype 1 chaddr 00e0.ed12.2168
*Mar  6 16:01:24.055:   DHCPD: interface = Vlan207
*Mar  6 16:01:24.055:   DHCPD: class id 4d53465420352e30
*Mar  6 16:01:24.055: DHCPD: Sending notification of DISCOVER:
*Mar  6 16:01:24.055:   DHCPD: htype 1 chaddr 00e0.ed12.2168
*Mar  6 16:01:24.055:   DHCPD: giaddr = 192.168.70.254
*Mar  6 16:01:24.055:   DHCPD: interface = Loopback1
*Mar  6 16:01:24.055:   DHCPD: class id 4d53465420352e30
*Mar  6 16:01:24.055: DHCPD: Sending notification of DISCOVER:
*Mar  6 16:01:24.055:   DHCPD: htype 1 chaddr 00e0.ed12.2168
*Mar  6 16:01:24.055:   DHCPD: giaddr = 192.168.70.254
*Mar  6 16:01:24.055:   DHCPD: interface = Loopback1
*Mar  6 16:01:24.055:   DHCPD: class id 4d53465420352e30

Just stuck at discover

Can you please post the vlan interface settings using "show run inter vlan 207"

Also, I would recommend adding the command "switchport mode access" to all of your non-trunk interfaces. That will add another layer of security and devices should connect faster because they don;t have to negotiate the connection.

Thanks

Hey thanks for your comments Andy

Here is the result

mbicl3sw01#sh run int vlan207
Building configuration...

Current configuration : 94 bytes
!
interface Vlan207
 description GusestWiFiUser
 ip address 192.168.70.254 255.255.255.0
end

This is really getting on my nerves now as I just cant seem to get cross vlan dhcp working at all through this switch. Ive given up trying to get DHCP served directly from the switch in lieu of using my main user DHCP server which sits on windows. Even that wont work!!!

Ok here is my config

User VLAN 201  192.168.25.0  SVi 192.168.25.245
On this VLAN I have a windows Domain server also hosting DHCP 192.168.25.21
My DHCP server has scope configured for 192.168.70.0
The windows domain server is hosted on a ESXI box which is connected to the switch via interface Port-channel1
Vlan configured appropriately on ESXI

VLAN 207 192.168.70.0 SVI 192.168.70.254
PC directly connected to switch port gi1/0/27 configured for this VLAN
Helper address configured for 192.168.25.21

I see in debug:

Sep 18 14:20:16.940: DHCPD: DHCPDISCOVER received from client 0063.6973.636f.2d30.3031.632e.3537.6633.2e33.6432.312d.4661.34 on interface Vlan207.
Sep 18 14:20:16.949: DHCPD: using received relay info.
Sep 18 14:20:16.949: DHCPD: Looking up binding using address 192.168.70.254
Sep 18 14:20:16.949: DHCPD: setting giaddr to 192.168.70.254.
Sep 18 14:20:16.949: DHCPD: BOOTREQUEST from 0063.6973.636f.2d30.3031.632e.3537.6633.2e33.6432.312d.4661.34 forwarded to 192.168.25.21.

that's it. On my dhcp server log I don't see any attempt for it to connect.

I can ping 192.168.25.21 from the switch

My switch config:


!
! Last configuration change at 12:22:11 UTC Mon Sep 18 2017 by root
! NVRAM config last updated at 14:11:07 UTC Mon Sep 18 2017 by root
!
version 12.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname mbicl3sw01
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$
enable password
!
username root privilege 15 secret 5
aaa new-model
!
!
!
!
!
aaa session-id common
switch 1 provision ws-c3750g-48ps
system mtu routing 1500
ip subnet-zero
ip routing
ip dhcp relay information trust-all
ip dhcp use vrf connected
!
ip dhcp pool VoiceVlan
   import all
   network 192.168.50.0 255.255.255.0
   dns-server 8.8.8.8
   default-router 192.168.50.254
   lease 0 2
!
!
ip dhcp-server 192.168.25.21
!
!
crypto pki trustpoint TP-self-signed-3343665408
 enrollment selfsigned
 subject-name cn=IOS-Self-Signed-Certificate-3343665408
 revocation-check none
 rsakeypair TP-self-signed-3343665408
!
!

!
!
!
port-channel load-balance src-dst-ip
!
!
spanning-tree mode pvst
spanning-tree etherchannel guard misconfig
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
!
!
interface Port-channel1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 201-210
 switchport mode trunk
!
interface GigabitEthernet1/0/1
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/2
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/3
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/4
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 201
 switchport mode trunk
 spanning-tree portfast
!
interface GigabitEthernet1/0/5
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/6
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/7
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/8
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/9
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/10
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/11
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/12
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/13
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/14
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/15
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/16
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/17
 switchport access vlan 203
 switchport mode access
!
interface GigabitEthernet1/0/18
 switchport access vlan 203
 switchport mode access
!
interface GigabitEthernet1/0/19
 switchport access vlan 203
 switchport mode access
 shutdown
!
interface GigabitEthernet1/0/20
 switchport access vlan 203
 switchport mode access
!
interface GigabitEthernet1/0/21
!
interface GigabitEthernet1/0/22
!
interface GigabitEthernet1/0/23
!
interface GigabitEthernet1/0/24
!
interface GigabitEthernet1/0/25
!
interface GigabitEthernet1/0/26
 switchport access vlan 208
!
interface GigabitEthernet1/0/27
 switchport access vlan 207
 switchport mode access
 spanning-tree portfast
!
interface GigabitEthernet1/0/28
 switchport access vlan 207
!
interface GigabitEthernet1/0/29
 shutdown
!
interface GigabitEthernet1/0/30
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 201-210
 switchport mode trunk
 channel-group 1 mode active
!
interface GigabitEthernet1/0/31
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 201-210
 switchport mode trunk
 channel-group 1 mode active
!
interface GigabitEthernet1/0/32
!
interface GigabitEthernet1/0/33
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/34
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/35
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/36
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/37
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/38
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/39
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/40
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/41
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/42
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/43
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/44
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/45
 switchport access vlan 207
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/46
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/47
 switchport access vlan 201
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/48
 switchport access vlan 204
 switchport mode access
 switchport voice vlan 202
 spanning-tree portfast
!
interface GigabitEthernet1/0/49
!
interface GigabitEthernet1/0/50
!
interface GigabitEthernet1/0/51
!
interface GigabitEthernet1/0/52
!
interface Vlan1
 ip address 192.168.25.9 255.255.255.0
 shutdown
!
interface Vlan201
 ip address 192.168.25.254 255.255.255.0
!
interface Vlan202
 description VoiceVlan
 ip address 192.168.50.254 255.255.255.0
!
interface Vlan204
 description ServerVlan
 ip address 192.168.30.254 255.255.255.0
!
interface Vlan205
 description FirewallInternalVlan
 ip address 192.168.40.254 255.255.255.0
!
interface Vlan206
 description ManagementVlan
 ip address 192.168.60.254 255.255.255.0
!
interface Vlan207
 description GusestWiFiUser
 ip address 192.168.70.254 255.255.255.0
 ip helper-address 192.168.25.21
!
interface Vlan208
 ip address 192.168.80.254 255.255.255.0
!
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.40.1

!
!
control-plane
!

!
end


I'm beginning to think this is linked with the original issue however I still haven't spotted my error or th ebug!

ip helper-address 192.168.25.21
points that dhcp server is configured and present in Vlan201 - 192.168.25.21
Is DHCP server present there?

Yes it is

try this commands

ip dhcp binding cleanup interval 600
ip dhcp conflict resolution interval 30

I solved it myself