VyOS 2026.03 (Stream) unable to initiate DHCP discover when connected to an ethernet switch in GNS3

Bugs
1

My version:

vyos@vyos:~$ sh ver
Version: VyOS 2026.03
Release train: circinus
Release flavor: generic

Built by: autobuild@vyos.net
Built on: Wed 18 Mar 2026 20:03 UTC
Build UUID: 3969e1c7-a4bb-459a-ac7f-54749c153d21
Build commit ID: 1cac4fd63750b0

Architecture: x86_64
Boot via: installed image
System type: KVM guest

Hardware vendor: QEMU
Hardware model: Ubuntu 26.04 PC (i440FX + PIIX, 1996)
Hardware S/N:
Hardware UUID: ede10114-b2a2-465a-9611-d525a6c90e4e

Copyright: VyOS maintainers and contributors

My interface config:

vyos@vyos# sh int
ethernet eth0 {
address dhcp
hw-id 0c:e1:01:14:00:00
}

My topology:

image
image451×463 18.5 KB

Switch config (default):

image
image718×373 11.4 KB

Expected behavior: The VyOS router eth0 interface gets an IP from DHCP, just like the Cisco router connected to the same switch does.

Actual behaviour: VyOS router is unable to get an IP from DHCP when connected to the switch. DHCP works when directly connected to the NAT node, but doesn’t even initiate a DHCP discover request when connected to the Ethernet switch in GNS3. The router claims it’s sending DHCP requests on eth0, but they don’t show up in the wireshark pcap.

Logs and PCAP attached. PCAP Setup:

image
image503×480 19.3 KB

VyOS-2026-03-Logs.txt (12.8 KB)

PCAP_Text.txt (6.3 KB)

PCAPNG File here.

2

P.S. Almost certainly a bug, since the rolling release don’t have a problem with this, and works absolutely perfectly.

image
image1099×787 51.9 KB

3

Bug report created: ⚓ T9017 VyOS 2026.03 (Stream) unable to initiate DHCP discover when connected to an ethernet switch in GNS3