When using:/etc/network/interfacesauto loiface lo inet loopbackauto eth0iface eth0 inet dhcpauto wlan0allow-hotplug wlan0iface wlan0 inet dhcpwpa-ssid <myssid>wpa-psk <mypasswd>why is the boot blocked for more than 1 minute if no ethernet cable is connected?Why doesn't it go to the next lines and use wlan0 instead ?I would like that if no ethernet cable is connected, the system doesn't wait so long, and try with wlan0 instead. How to do that?I'm using Debian Jessie with networking.service.
Two networking interfaces trying to get an IP via DHCP
networking;ethernet;systemd
You should change auto eth0 to allow-hotplug eth0 in your /etc/network/interfaces. This would keep your system away from trying to get address by DHCP when interface isn't connected. This should fix the problem.Also, you can set lower timeout to DHCP client. You may set timeout 3; in /etc/dhcp/dhclient.conf.It will set 3 seconds timeout for getting IP over DHCP.Longer time should make process more reliable on slower networks, but takes more time. Shorter time could left you without an address when network is on load.