I need to write a "one-liner" in /etc/network/interfaces that ensures that when eth1 goes up/down a file /var/log/network.log is written with something like that UP/DOWN [DATE/TIME]
EX: UP [10-12-2012/21:30:00]
The format is [DD-MM-YY/HH-MM-SS]
If eth1 is active put in /var/log/network.log UP [DATE/TIME] if eth1 is DOWN put in /var/log/network.log DOWN [DATE/TIME]