- Written by Augusto Wong
- Posted on February 17, 2021
- Updated on January 16, 2026
- 16707 Views
The DHCP relay feature, forwards DHCP packets between a client and the DHCP server when the server is not in the same broadcast domain as the client. The DHCP relay should be configured on the gateway interface (SVI/ L3 interface) for the clients.
- Written by Richard Zhang
- Posted on December 22, 2020
- Updated on December 22, 2020
- 12715 Views
EOS DHCP relay agent forwards all the DHCP requests from the clients using the primary IP address of the interface as
- Written by VICTOR WEN
- Posted on April 7, 2021
- Updated on January 5, 2026
- 14099 Views
EOS supports the DHCP Relay feature, which relays DHCP Requests/Responses between DHCP clients and DHCP servers in different subnets. However, the DHCP server does not have visibility of where the request originated from and can only make IP address allocation decisions based on the client MAC address alone (client MAC address is included in the DHCP packet as part of the payload). To remedy that, DHCP Option-82 was formalized to allow relay agents to include Remote ID and Circuit ID so that DHCP servers can apply a more intelligent allocation policy.
- Written by Xujia Cao
- Posted on August 16, 2018
- Updated on May 4, 2020
- 10934 Views
DHCP relay agent uses one of the addresses configured on the interface as the source IP when relaying messages to the
- Written by Pratik Mangalore
- Posted on December 14, 2020
- Updated on November 5, 2025
- 19411 Views
IP Locking is an EOS feature configured on an Ethernet Layer 2 port. When enabled, it ensures that a port will only permit IP and ARP packets with IP source addresses that have been authorized. As of EOS-4.25.0F release update, IP Locking can run in two modes - IPv4 Locking (which will be referred to as IP Locking) and IPv6 Locking, which can be configured using the commands mentioned in the below sections. IP Locking prevents another host on a different interface from claiming ownership of an IP address through either IP or ARP spoofing.
- Written by Kundan Sen
- Posted on November 12, 2019
- Updated on November 12, 2019
- 9832 Views
EOS 4.23.0F adds support for redistributing DHCPv6 routes in IS IS when using the multi agent routing protocol mode.
