MyFerryLink strikers are reacting to the the refusal of their company's owner, Eurotunnel, to pay off its 6.2-million-euro debt, making it impossible to distribute their salaries in July.
Strikers decided to allow vessels from the rival company DFDS to continue operating.
In July strikers paralysed Eurotunnel traffic by blocking the Calais port and stopping thousands of trucks crossing the English Channel.
During the last ferry strike, migrants had taken advantage of the situation to try to climb on to vehicles headed for the UK.
Some 600 ferry workers face an uncertain future after Eurotunnel announced it would rent two out of its three ferries to competitor DFDS, which hopes to buy them all eventually.