Today, resmoke deploys the necessary routers specified by “num_routers” or the default ones to run testing suites.

In the context of the embedded router, each node exposes a router, and resmoke chooses some of them to use on the testing suites.

To follow the correct deployment, we enforce the first router to be one node of the config server replica set. This is because the router service is enabled on shards that have the shard identity document.

Because of that, the first router of the list of mongos available for testing is always the configsvr, we are going to stress too much the config server and lose coverage as testing the router port on primary/secondary shards.

Goal

We need to randomize the list of routers available for testing after adding all the shards at resmoke in order to have better coverage.

References

• ShardedClusterFixture
• Where mongoS are installed

Estimation

• User impact: no impact.
• Raw Estimation (man day): 2