An App Requires a Specific Host Port

Generally, it is not recommended to configure your apps to depend on a particular host port because it constraints scheduling. We know that it is sometimes only avoidable at great cost so Marathon allows you to specify a required host port by:

Marathon can only use offers for such offers that include the required host ports. By default, Mesos agents do NOT offer all ports, so if you require port e.g. 80 you have to make sure that this port is offered by the agent. You can make all ports from 1 to 65000 available to the mesos agent by using --resources=ports:[1-65000]. Please make sure that only tasks scheduled by Mesos use ports in the specified range! You can find the relevant configuration options for the Mesos agent here.