Boland came through the ranks at City and made 71 appearances for the first team before he joined Cardiff in 1999.
The Irishman last played for Hartlepool United in 2008 and told their club website: "I've got used to not playing. I wouldn't be able to do myself justice.
"I want to stay in the sporting side of things, whether it be in coaching, fitness or working in the community."
All at Covsupport News Service wish him all the best with whatever he does next.