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Dhcp Relay Agent And Acl On Sw 3750, DHCP Relay Agent and ACL on Sw 3750

Dear All;

I have implemented ACL apply on SW 3750 and want to set DCHP Relay agent to forward to DCHP server that is different subnet. I have 2 VLAN . DCHP is on VLAN1 and want VLAN 2 can get ip from DCHP server on VLAN

  1. So that I need to set up dchp relay agent on VLAN2 but my company have policy to apply ACL on VLAN 2 but it is not work to set up dchp relay agent. Anyone help me ,what about I need to do permitt rule on ACL to dchp relay agent work?

Thanks and Regards; Vimokh

Reply to
Vimokh
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DHCP version 4 uses UDP with source IP address 0.0.0.0,destinaion address 255.255.255.255, source UDP port 68 and destination UDP port 67 to send a DHCPDISCOVER request to the DHCP server.

The DHCP server will then unicast a DHCP Offer packet back to the DHCP relay agent which will forward it to the DHCP client.

The DHCP client will then sent a DHCP request to the Dhcp server indicating that it will use the offered IP address.

The DHCP server will unicast a DHCP acknowledgement to the DHCP client.

The access list smust be modified to permit the DHCP packets described.

Reply to
Merv

Also, clients renewing their lease unicast a DHCPREQUEST to the server that assigned them their lease. You need to account for this on an ingress ACL as well, i.e.

! permit udp eq 68 host eq 67 !

Reply to
Martin Gallagher

Thank you all for your information.

Vimokh Mart>

Reply to
Vimokh

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