WPA on Linux

I have used Ubuntu's builtin WYSIAYG network manager. At some point I needed some more control over my network interfaces. I wanted a dhcpd to listen on eth0, and wanted my wlan to connect to my router. So I disabled the network manager:
sudo /etc/init.d/network-manager stop
And configuring the wpa:

wpa_passphrase ssid passphrase > /etc/wpa_supplicant/wpa_supplicant.conf
wpa_supplicant -iwlan0 -c/etc/wpa_supplicant/wpa_supplicant.conf &
dhclient wlan0