Can't find Intel Wireless-N 1000 after waking from sleep

Note: iwlagn was renamed to iwlwifi in Ubuntu 12.04 and later, so replace appropriately in the below steps if you are on 12.04.

This line, immediately after the PHY(sical) wifi interface is brought up, tells us about the source of your problem:

[29054.603501] iwlagn 0000:0d:00.0: fail to flush all tx fifo queues

• It is related to this bug, even though you have a 1000 and not a 6250.

Solution:

• After boot:
  1. sudo modprobe -r iwlagn
  2. sudo modprobe iwlagn bt_coex_active=0
  3. Suspend/wake -- does it work now?

If it does, make it permanent by adding a file /etc/modprobe.d/iwl.conf, containing only this line:

options iwlagn bt_coex_active=0