Scottish international Mark Burchill heads the list of players on their way out of Fratton Park.
Redknapp has also told defenders Jamie Vincent and Lewis Buxton, midfielders Carl Robinson, Richard Hughes, Courtney Pitt and Neil Barrett and striker Rowan Vine that they are surplus to requirements.
"We have several players who are not going to make it in The Premiership," said Redknapp.
"It is only fair we give them a chance to find alternative clubs."
The eight join Carl Tiler, Luke Nightingale, Lee Molyneaux, Tom White and Jason Crowe in being told they can leave the club.
