I have a media and PVR server running ubuntu 16.04 that sporadically loses its wired connectivity (the IP drops off the ifconfig output; the icon on the desktop indicates that it's connected but it's not). The interface is dhcp, but is statically assigned from the router. If I don't catch that it's down for hours or days, I miss recording shows onto it (which saddens the wife).
After reading numerous approaches across askubuntu and elsewhere, my solution was going to be simply to add "ifup -a" to cron.hourly. Is there a performance hit or any other impacts of doing this? Is there a better or "approved" way of checking and restarting network interfaces automatically? I don't know why it drops in the first place-- the wire stays connected and the machine is directly connected to my main (unmanaged) switch.
/etc/network/interfaces:
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
auto enp0s10
iface lo inet loopback
iface enp0s10 inet dhcp
allow-hotplug
instead ofauto
for the Ethernet interface. It should then automatically recover when reconnected and attempt to renegotiate for the IP. (This is what I do on several systems with non-Network-Manager-managed Ethernet interfaces). I'll bet its losing the IP because of some other reason, such as the wire temporarily losing connectivity or such, and as such allowing as hotplug will help a little.