The Mongo Driver, No Failover and Compose.io's New MongoDB Offering

deployment
1

Compose.io has rolled out a new iteration of its MongoDB as a Service offering. And it seems that existing Node drivers don’t work with it (i.e.: support failover):

Some drivers like Node (and Meteor) are not able to handle failover between mongos nodes.

So they suggest that instead of using the usual connection string (with failover options):

mongodb://<user>:<password>@aws-us-east-1-portal.88.dblayer.com:88888,aws-us-east-1-portal.99.dblayer.com:99999/test-deployment-todos?ssl=true

… to use one of the following

mongodb://<user>:<password>@aws-us-east-1-portal.88.dblayer.com:88888/test-deployment-todos?ssl=true
mongodb://<user>:<password>@aws-us-east-1-portal.99.dblayer.com:99999/test-deployment-todos?ssl=true

which does not support failover scenarios.

I guess this was more of a statement than anything. The silly question that follows is… Any news about when we can expect driver support?

1 Like
2

Meteor uses the MongoDB Node.JS Driver; maybe try opening an issue with that project first (or submit a PR), to get it updated to support multiple hosts (without assuming it’s a replicaset).

For anyone else interested, there is a good breakdown of the issue here: Connecting to the new MongoDB at Compose

3

My application crashed today because of that. The primary db failed and galaxy did not handle the failover to default on the other possible base.

Any news on that?

4

Just had this happen to me too. Any resolution or tips to prevent in the future?

5

What version of Meteor are you using?

To the best of my knowledge there was an issue with an old version of the Nodejs MongoDB driver (== an old version of Meteor). However that was fixed over a year ago I think. I’ve not seen any issues with handling failover in a long time.

6

I was on 1.4.4.1…
Thanks for the follow-up. I’m looking into the Mongo Logs more now.