Hi. I did som further investigation here, and I think I've figured out what happens in networkd here.
Aug 21 10:54:45 nettest1 systemd-networkd[5463]: ens3: Removing address: 2001:700:1d00:ec00:5054:ff:fe49:4bc9/64 (valid for 4w 2d)
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Removing address: 10.212.128.84/24 (valid for 11h 57min 54s)
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: Sent message type=signal sender=n/a destination=n/a path=/org/freedesktop/network1/link/_32 interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=17 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: Sent message type=signal sender=n/a destination=n/a path=/org/freedesktop/network1 interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=18 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Routing policy rule configured
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Could not set route: Network is unreachable
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Routes set
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Adding address: 10.212.128.84/24 (valid for 12h)
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: Sent message type=signal sender=n/a destination=n/a path=/org/freedesktop/network1/link/_32 interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=19 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: Sent message type=signal sender=n/a destination=n/a path=/org/freedesktop/network1 interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=20 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
Aug 21 10:54:46 nettest1 systemd-networkd[5463]: ens3: Configured
Basically it seems like networkd does the following on "netplan apply":
1) Remove every address
2) Add routes - which of course will fail with "network is unreachable" because the interfaces don't have an address yet
3) Adding the addresses
Hi. I did som further investigation here, and I think I've figured out what happens in networkd here.
Aug 21 10:54:45 nettest1 systemd- networkd[ 5463]: ens3: Removing address: 2001:700: 1d00:ec00: 5054:ff: fe49:4bc9/ 64 (valid for 4w 2d) networkd[ 5463]: ens3: Removing address: 10.212.128.84/24 (valid for 11h 57min 54s) networkd[ 5463]: Sent message type=signal sender=n/a destination=n/a path=/org/ freedesktop/ network1/ link/_32 interface= org.freedesktop .DBus.Propertie s member= PropertiesChang ed cookie=17 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a networkd[ 5463]: Sent message type=signal sender=n/a destination=n/a path=/org/ freedesktop/ network1 interface= org.freedesktop .DBus.Propertie s member= PropertiesChang ed cookie=18 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a networkd[ 5463]: ens3: Routing policy rule configured networkd[ 5463]: ens3: Could not set route: Network is unreachable networkd[ 5463]: ens3: Routes set networkd[ 5463]: ens3: Adding address: 10.212.128.84/24 (valid for 12h) networkd[ 5463]: Sent message type=signal sender=n/a destination=n/a path=/org/ freedesktop/ network1/ link/_32 interface= org.freedesktop .DBus.Propertie s member= PropertiesChang ed cookie=19 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a networkd[ 5463]: Sent message type=signal sender=n/a destination=n/a path=/org/ freedesktop/ network1 interface= org.freedesktop .DBus.Propertie s member= PropertiesChang ed cookie=20 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a networkd[ 5463]: ens3: Configured
Aug 21 10:54:46 nettest1 systemd-
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Basically it seems like networkd does the following on "netplan apply":
1) Remove every address
2) Add routes - which of course will fail with "network is unreachable" because the interfaces don't have an address yet
3) Adding the addresses