Same issue here:
Multiple Ubuntu 20.04.1 LTS (Desktops & Servers) affected:
Only IPv6 address via DHCP after reboot, no IPv4, thus no (internal) DNS resolution (network shares fail when binded via hostnames).
As a workaround all network shares are now mounted via IP address and dhclient has to be called after each reboot manually (to get SLURM workloadmanager working).
Same issue here:
Multiple Ubuntu 20.04.1 LTS (Desktops & Servers) affected:
Only IPv6 address via DHCP after reboot, no IPv4, thus no (internal) DNS resolution (network shares fail when binded via hostnames).
As a workaround all network shares are now mounted via IP address and dhclient has to be called after each reboot manually (to get SLURM workloadmanager working).