The opportunity to volunteer as a server is open to anyone of any age; although for young people it is thought appropriate that individuals should be confirmed and for older people it is important to be able to stand for long periods as well as walk straight!
The basic duty of a server is to assist with the liturgies held in the Cathedral. This involves leading processions (with cross and candles) and assisting in other ways during the Eucharist, eg receiving the collection and preparing the altar at the offertory. Servers are also required for 10.30am Sung Evensong on Sundays and other services on feast days. Training is given.
As for the time commitment involved, the Head Server prepares a rota which indicates who will do what at any particular service. The regularity of duties is entirely dependent on the individual's preference. Some will have duties at their parish church, while others may live some distance away and are less regular. All these matters are taken into account, but reliability is essential.
Most of the existing team are regular members of the congregation who happen also to be servers. This works well since they remain part of the community whether in the sanctuary or the pew, but the two do not have to go together.