[MESOS-6763] Add heartbeats to both input/output connections in IOSwitchboard

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.2.0
• Labels: debugging mesosphere
• Target Version/s: 1.2.0
• Epic Link: Mesos Container Attach/Exec
• Story Points: 2
• Assignee: Kevin Klues
• Reporter: Kevin Klues
• Shepherd: Vinod Kone
• Created: 09/Dec/16 01:17
• Updated: 15/Dec/16 02:03
• Resolved: 15/Dec/16 02:03

Description

Some networks will kill idle connections if no data is transfered over them within a set amount of time. For example, using AWS's Elastic Load Balancer (ELB), the default time to kill a connection is only 60s! Because of this, we need a way to send application level heartbeats to keep these connections alive for any long running LAUNCH_NESTED_CONTAINER_SESSION, ATTACH_CONTAINER_INPUT and ATTACH_CONTAINER_OUTPUT calls.

We should serve these heartbeats from the IOSwitchboard server rather than the agent handlers since the agent essentially acts as a proxy and the heartbeats should originate from the actual server being communicated with.