I have an Ubuntu 18.04 VM on Azure with 2 NIC's on the same subnet. Both have public IPs but only 1 can access the internet. I tried to modify the netplan file but can only seem to get one or the other to work.
Here is the route table:
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 _gateway 255.255.255.255 UGH 100 0 0 eth1
0.0.0.0 _gateway 255.255.255.255 UGH 100 0 0 eth0
default _gateway 0.0.0.0 UG 100 0 0 eth0
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
168.63.129.16 _gateway 255.255.255.255 UGH 100 0 0 eth0
169.254.169.254 _gateway 255.255.255.255 UGH 100 0 0 eth0
And the netplan:
network:
ethernets:
eth0:
dhcp4: true
routes:
- to: 0.0.0.0
via: 10.0.0.1
metric: 100
# dhcp4-overrides:
#route-metric: 100
#use-routes: false
dhcp6: false
match:
driver: hv_netvsc
macaddress: 60:45:bd:c0:aa:ff
set-name: eth0
eth1:
dhcp4: true
routes:
- to: 0.0.0.0
via: 10.0.0.1
metric: 100
#dhcp4-overrides:
# route-metric: 200
dhcp6: false
match:
driver: hv_netvsc
macaddress: 60:45:bd:c7:6a:d7
set-name: eth1
version: 2
In this config I can only access (ping) the internet from eth0. I tried to override the DHCP route and set the default on 1 nic only but that didn't seem to work. Both NIC have static IPs in Azure. Appreciate any tips.
edit:
So interestingly, I updated my netplan and set static IPs and disable dhcpv4 but systemd is still inherting the route from DHCP so I believe that is the issue but I am not sure how else to disable it if I set it to disabled in netplan
systemd-networkd[2711]: eth1: DHCPv4 address 10.0.0.5/24
systemd-networkd[2711]: eth1: DHCP: No routes received from DHCP server: No data available
systemd-networkd[2711]: eth1: Configured
systemd-networkd[2711]: eth0: DHCPv4 address 10.0.0.4/24 via 10.0.0.1
systemd-networkd[2711]: eth0: Configured
