I tried using wpa-supplicants to be able to connect to multiple WiFi's (not simultaneously).
This only works with manual it seems and not with DHCP. Writing the SSID and the password directly in /etc/network/interfaces works for one network.
From the interfaces file it seems only one network can be specified. Any ideas?
EDIT: By 2 networks I mean my wireless home network and e.g. the network at university. I want my pi to have a (un)ordered list of networks and I want to connect to one available. It is enough, when this happens on startup, but it would be nice if it tries to reconnect, when the connection is lost..
