DHCP on 3750

[makpak111]

Hi team,

We want to configure DHCP Server on 3750 Switch in which there are number of vlans but we want to configure DHCP pool for only one vlan.

can we configure DHCP server on 3750 with exclude ip address for same vlan.

Pls Suggest or share any supported document.

Regards

Mak.

[Peter Paluch]

Mak,

If I understand you correctly then you simply want to create a DHCP pool for one (and only one) of your VLANs. Is that correct? That is supported of course:

ip dhcp pool V99
 network 192.168.99.0 /24
 default-router 192.168.99.254
 dns-server 4.2.2.2
ip dhcp excluded address 192.168.99.0 192.168.99.100

I am not sure if this helps so please ask further.

Best regards,

Peter

[Ajay Patel]

Hi Mak,

As Peter Suggested you DHCP configuration;

ip dhcp pool V99
 network 192.168.99.0 /24
 default-router 192.168.99.254
 dns-server 4.2.2.2
ip dhcp excluded address 192.168.99.0 192.168.99.100

Above configuration will work fine for all the Vlan but these would not be limited only for one Vlan; need to filter.

if you could elobrate you exact requirement that would be great.

Thank you

Ajay

[tylerlucas]

The above configuration will only give DHCP leases connected to the corresponding LAN interface.

Hypothetically:

int g0/1

ip address 10.10.10.254 255.255.255.0

no shut

int g0/2

ip address 192.168.99.254 255.255.255.0

no shut

If you used the above DHCP configuration, only hosts connected to g0/2 would receive DHCP addresses, because they fall within the same network.

[andtoth]

The same applies to vlan interfaces. If the IP address which falls within the DHCP range is assigned to a vlan interface, the switch will give IP addresses from that subnet (configured in the pool) to ports belonging to that vlan.

Andras

[Ajay Patel]

Hi Mak,

Please include below command on the configuration:

Service DHCP (will start DHCP service on Switch)

Thank you

Ajay