Is ONE PIECE episode 217 filler?
Canon No, episode 217 of ONE PIECE is canon.
#217
The Captains Square Off! The Final Combat Round!
キャプテン対決！最終戦コンバット！
Aired 16 Jan 2005
Mochibayo compiled this list from MyAnimeList's labels, because MyAnimeList's episode data is not reaching us at the moment.