fab -h
will show you all the options, you can also read them here.
In particular, and I quote,
-p PASSWORD, --password=PASSWORD
Sets env.password to the given string;
it will then be used as the default
password when making SSH connections
or calling the sudo program.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…