The MACsec SSU feature enables a switch to undergo an In-Service Software Upgrade to a newer EOS version without disrupting existing MACsec traffic. Previously, the MACsec control plane agent would restart during SSU without previous state information. This lengthy cold reboot caused sessions to drop because MKA (MACsec Key Agreement) protocol packets (MKPDUs) were not sent, leading to traffic loss based on configured security policies.

In VXLAN networks, broadcast DHCP requests are head-end-replicated to all VXLAN tunnel endpoints (VTEP). If a DHCP relay helper address is configured on more than one VTEP, each such VTEP relays the DHCP request to the configured DHCP server. This could potentially overwhelm the DHCP server as it would receive multiple copies of broadcast packets originated from a host connected to one of the VTEPs.

The EOS DHCP relay agent now supports forwarding of DHCP requests to DHCP servers located in a different VRF to the DHCP