McDermott, who is the IRFU's Elite Player Development Manager will be assisted by Pat Murray while the squad manager will be David Haslett.
Host nation Scotland kick off their campaign against 2002 champions South Africa, and also face England and Russia in their pool matches.
Earlier that day (Fri 11th June), Ireland open their account with a game against Tonga at New Anniesland Stadium in Glasgow (ko 5pm).
Ireland U21 Management. Manager - David HaslettCoach - Mark McDermottAssistant Coach - Pat Murray