Appsmith server is not starting because of MongoDB exception

Question

My Appsmith instance just upgraded to v1.6.4 and it's not booting up anymore. In the logs, I can see the exception below:

Caused by: com.mongodb.MongoCommandException: Command failed with error 17 (ProtocolError): 'Attempt to switch database target during SASL authentication.' on server mongo:27017. The full response is {"ok": 0.0, "errmsg": "Attempt to switch database target during SASL authentication.", "code": 17, "codeName": "ProtocolError"}

Is there anything I can do to bring up my Appsmith instance?

Answer 1

This is a breaking change that was introduced in v1.6.4 of Appsmith because of Spring library upgrades. A complete fix is described at: https://docs.appsmith.com/troubleshooting-guide/deployment-errors#server-not-booting-because-of-mongocommandexception

Step 1: Edit MongoDB URI

Adding &authSource=admin to the end of your APPSMITH_MONGODB_URI variable’s value in your docker.env file. For example, in your docker.env file, if you have the following line:

# Old config
APPSMITH_MONGODB_URI=mongodb://<your_username>:<your_password>@mongo/appsmith?retryWrites=true

Change it to the following (notice the only change is &authSource=admin. Do NOT copy-paste this whole line. Only add the &authSource=admin part to your existing value.

# New config
APPSMITH_MONGODB_URI=mongodb://<your_username>:<your_password>@mongo/appsmith?retryWrites=true&authSource=admin

Save the file.

Step 2: Restart server

Now restart your container with the following command:

sudo docker-compose up -d --force-recreate appsmith-internal-server

In a minute or two, the server should now come up and be ready.