After updating our mongodb package to 3.4.0 our production/staging servers cannot connect to their database any more.

Here's the connection string for staging with project-specific information removed:

mongodb://xxx:xxx@xxxx.servers.mongodirector.com:27017/staging?ssl=true&connectTimeoutMS=10000&authSource=admin&authMechanism=SCRAM-SHA-1

This is how we construct the connection:

const client = new MongoClient(mongoUrl, {
{{ connectTimeoutMS,}}
{{ socketTimeoutMS,}}
{{ useNewUrlParser: true,}}
{{ useUnifiedTopology: true,}}
});

This is the error output we get with 3.4.0 of the library:

MongoTimeoutError: Server selection timed out after 30000 ms
{{ at Timeout._onTimeout (/home/ubuntu/app/node_modules/mongodb/lib/core/sdam/server_selection.js:309:9)}}
{{ at listOnTimeout (internal/timers.js:531:17)}}
{{ at processTimers (internal/timers.js:475:7)}}

It works correctly with 3.3.5

All systems affected are running some version of linux.