Unless you continue to remember it

The dynamic device interface for Linux is called udev.  Generally it works without complaint or frustration but it does have some interesting side effects if you are doing more involved system configuration.  The one that tripped me up today is that udev keeps a record of every nic card that has been dynamically created during it’s lifetime.  For example, if you are using wireless USB nic (see my post yesterday) and you plug in a different one than you used before; the new nic ID is going to be wlan1 instead of wlan0.  Generally nobody would care; but in this case I did.  Thankfully modifying these records is pretty easy.  The device history is stored in /etc/udev/rules.d/70-persistent-net.rules and can be modified by hand.  Just change the wlan1 to wlan0 and delete the other entry.

Once again, text file configuration is FREAKING AWESOME!