SG500X-48 DHCP issue

[aaau20410]

I created 4 VLAN on SG500X-48 switch, with default VLAN 1 disabled.
(AD, DHCP & DNS server IP = 192.168.11.88, Default Gateway IP = 192.168.11.1)

DHCP server has scoops for VLAN 11, VLAN 21, VLAN 31 & VLAN 41

VLAN 11 - new default VLAN for AD, DHCP & DNS server (192.168.11.0/24)
VLAN 21 - Voice-VLAN (192.168.21.0/24)
VLAN 31 - Prod-VLAN (192.168.31.0/24)
VLAN 41 - Dev-LVAN (192.168.41.0/24)

VLAN 21, 31 & 41 cannot obtain auto IP addresses from VLAN 11's DHCP server

I have enabled ip helper-address 192.168.11.88 255.255.255.255 on each VLAN, but "show run" command results "ip helper-address 192.168.11.88 255.255.255.255 37 42 49 53 137 138"

If I added port 67 & 68 to the end of the "ip helper-address ip helper-address 192.168.11.88 255.255.255.255 67 68", it returns the following error "Ports 67-68 are reserved for BOOTP/DHCP"

If anyone can help shed some light I would really appreciate it.

Thanks in advance.

[christopher.tatton]

Some things to check, and I don't mean to offend if some of them seem obvious but you didn't list it above.

• Is the switch in L3 mode?
• Did you create SVIs for each of the VLANs?

[DJX995 · Accepted solution]

The Cisco SMB switches operate differently.

The IP Helper command on these units is just for UDP forwarding of odd services.

There are dedicated commands for DHCP relay:

ip dhcp relay address XXX.XX.XX.XX
ip dhcp relay enable
ip dhcp information option
ipv6 dhcp relay destination XXXX:XXX:XXXX:XX:XX

Then, on each SVI, you enable DHCP Relay as needed (you do not enable DHCP relay on the SVI directly connected to the DHCP server):

interface vlan XX
 ip dhcp relay enable
 ipv6 dhcp relay destination

[zeeyad]

What will be the command for ipv4 addresses? Shall I just replace ipv6 with ipv4 on these commands?