AWS Lambda 连接 DocumentDb 实例得到 MongoServerSelectionError: getaddrinfo EAI_AGAIN

Question

Got following error logs when trying to connecting lambda to documentdb.

 TART RequestId: 0946e4e9-9364-4af2-9802-7ea2d8b946d5 Version: $LATEST 2021-08-18T16:25:11.958Z 0946e4e9-9364-4af2-9802-7ea2d8b946d5 INFO insideHandler 2021-08-18T16:25:42.296Z 0946e4e9-9364-4af2-9802-7ea2d8b946d5 ERROR MongoServerSelectionError: getaddrinfo EAI_AGAIN sample-dev-01-instance1.abcde.us-east-1.docdb.amazonaws.com at Timeout._onTimeout (/var/task/node_modules/mongodb/lib/sdam/topology.js:325:38) at listOnTimeout (internal/timers.js:557:17) at processTimers (internal/timers.js:500:7) { reason: TopologyDescription { type: 'Unknown', servers: Map(1) { 'sample-dev-01-instance1.abcde.us-east-1.docdb.amazonaws.com:27017' => [ServerDescription] }, stale: false, compatible: true, heartbeatFrequencyMS: 10000, localThresholdMS: 15, logicalSessionTimeoutMinutes: undefined } }

the VPC of lambda is the same as documentdb instance. The nodejs code connects the instance successfully when running in local but has the issue in lambda.

 const { MongoClient } = require('mongodb'); exports.handler = async(event, context) => { console.log("insideHandler"); const uri = 'mongodb://username:password@sample-dev-01-instance1.abcde.us-east-1.docdb.amazonaws.com:27017'; const client = new MongoClient(uri, { useNewUrlParser: true, ssl: true, tlsCAFile: `rds-combined-ca-bundle.pem`, //Specify the DocDB; cert retryWrites: false }); try { await client.connect(); console.log("connect successfully"); return { statusCode: 200, body: JSON.stringify({ message: 'connect successfully' }) } } catch (e) { console.error(e); } };

enter code here

Answer 1

EAI_AGAIN is a DNS lookup timed out error, means it is a.network connectivity error or proxy related error. Can you confirm whether the Lambda function is using the same security group as the DocumentDB cluster?