DCHP Problem multiple VLANS

[MonacoFranze]

Hello,

we made some changes on a Cisco Catalyst SG500 (L 3) . For seperating hardware we configured 2 VLANS.

VLAN 20 for the normal traffic

VLAN 30 for specific Hardware devices -> at 2 ports (GiInt)

There are also some DHCP pools with hardware-address bindings (e.g. one special device).

After these Changes the Hardwaredevice from VLAN 43 ( with MAC-Address binding Option) is not reachable anymore.

So my suggestion is:

Normaly there shouldn`t be any problems with 2 VLANS using the same DHCP. They schould use the native DHCP (nothing configured on this) by default.

Am I (networking beginner) totally wrong or did i just forget one simple step in my loigic?

Thanks

[umeshpathak]

As far As i understand ,you have configure two vlan with one DHCP pool.If my udnerstanding is correct then

1.The basic need of vlan was to segment the network,which does not meet if device in two vlans use the same IP segment.

2.If you have read you need a router/L3 to communication between vlans ,which means they can not communicate directly.So definitely you need different IP subnet for each vlan.

[Richard Burts]

I am somewhat confused. You tell us about configuring 2 vlans (20 and 30) and then you tel us about a device in vlan 43. How many vlans are there? And what are the various vlans? You mention some DHCP pools but give us no detail about them.

You tell us the Hardware device from VLAN 43 is not reachable. What is this device? Is it getting an IP address? If so what address, what mask, and what gateway? Is the device able to ping its gateway?

[IP_Cartel]

can this device do ip helper address under the SVI?