Setting up networking...done. Setting up IP spoofing protection: rp_filter. Configuring network interfaces.../etc/network/interfaces:17: duplicate interface ifup: couldn't read interfaces file "/etc/network/interfaces" done.
インターフェースがダブってる って何だよ
cat /etc/network/interfaces
auto eth0
iface eth0 inet static
address 192.168.2.21
netmask 255.255.255.0
auto eth0:0
iface eth0 inet static
address 172.16.101.28
netmask 255.255.0.0インターフェースがダブってた