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Problems trying to migrating ports to a new Vlan using an externar DHCP server

Hello, here is the thing. I have the following configuration in my Core Switch:

interface Vlan1
 ip address 10.24.74.1 255.255.254.0 secondary
 ip address 192.0.2.54 255.255.255.0
 ip helper-address 10.24.86.22
 no ip redirects

As you see, we are using an external DHCP server for the Vlan1 and it is working:

Internet  192.0.2.98              0   3c97.0e23.3d8d  ARPA   Vlan1

Internet  192.0.2.194             0   e89a.8f77.36a0  ARPA   Vlan1
Internet  192.0.2.195             0   e89a.8f77.01ab  ARPA   Vlan1
Internet  192.0.2.198             2   001c.25de.acaa  ARPA   Vlan1
Internet  192.0.2.199             0   d8eb.97a6.30a4  ARPA   Vlan1
Internet  192.0.2.196             0   f0de.f1f1.1e06  ARPA   Vlan1
Internet  192.0.2.203             0   e89a.8f77.016f  ARPA   Vlan1
Internet  192.0.2.207             4   d0c7.89d6.3ba3  ARPA   Vlan1
Internet  192.0.2.211             0   4437.e636.7ef7  ARPA   Vlan1

But, when a try to migrate this port to a new Vlan (Vlan50), I got the following issue: 

001290: Jul 23 08:27:44.705 GMT: DHCPD: DHCPREQUEST received from client 013c.970e.233d.8d.
001291: Jul 23 08:27:44.705 GMT: DHCPD: client has moved to a new subnet.
001292: Jul 23 08:27:44.705 GMT: DHCPD: Sending DHCPNAK to client 013c.970e.233d.8d.
001293: Jul 23 08:27:44.705 GMT: DHCPD: broadcasting BOOTREPLY to client 3c97.0e23.3d8d.
001294: Jul 23 08:27:44.725 GMT: dhcp_snooping_get_ingress_port: Interface src_index 0xF
001295: Jul 23 08:27:44.725 GMT: DHCPD: DHCPDISCOVER received from client 013c.970e.233d.8d on interface Vlan50.
001296: Jul 23 08:27:44.725 GMT: DHCPD: there is no address pool for 10.24.76.1.
001297: Jul 23 08:27:44.725 GMT: DHCPD: setting giaddr to 10.24.76.1.
001298: Jul 23 08:27:44.725 GMT: DHCPD: BOOTREQUEST from 013c.970e.233d.8d forwarded to 10.24.86.21.

Any suggestions,

Thank you in advance,

1 REPLY
Silver

001294: Jul 23 08:27:44.725

001294: Jul 23 08:27:44.725 GMT: dhcp_snooping_get_ingress_port: Interface src_index 0xF

Snooping is enabled, trust the port where the DHCP server is connected


Or, configure the vlan where the server is, your helper-address will help filter the trusted DHCP servers

 

#ip dhcp snooping vlan 1,50

#interface range vlan 1-10
  #ip helper-address <IP>         -Point to DHCP

 

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