I'm not sure what you guys are saying....
It means a suspension. Dsus2 is a Dmajor with a suspended second.
D-F#-A-E
That reads incorrectly. The Sus designition indicates that the chord has no traditional third.
D-E-A is Dsus2
D-G-A is Dsus4
Sus2 and Sus4 are the only type of Sus chords. Sus is short for suspended 3rd. Meaning that the chord should resolve (traditionally speaking of course) to D (major triad).
Sus chords can not contain the major or minor 3rd, in this case F or F#.
Otherwise they would be called Dadd9 (DF#AE) or Dadd11 (DF#AG).