Hi,

The upgrade guide for Ops Manager 2.0 should be improved to cover upgrading installations where there are dedicated Backup Daemon hosts running Ops Manager 1.8 or 1.6.

In particular there is a step missing before step 6. Starting the mongodb-mms service on each machine will use the default conf-mms.properties file that includes the parameter:

mongo.mongoUri=mongodb://127.0.0.1:27017/?maxPoolSize=150

The service mongodb-mms would not start on all the hosts that are not running an application database on the same machine (127.0.0.1), port 27017:

# service mongodb-mms start
Starting pre-flight checks
Failure to connect to configured mongo instance: Config{loadBalance=false, encryptedCredentials=false, ssl='false', dbNames='[mmsdb, mmsdbprovisionlog, mmsdbautomation, mmsdbserverlog, mmsdbpings, mmsdbprofile, mmsdbrrd, mmsdbconfig, mmsdbjobs, mmsdbagentlog, mmsdbbilling, backuplogs, mmsdbautomationlog, cloudconf, backupdb, mmsdbprovisioning, mmsdbqueues]', uri=mongodb://127.0.0.1:27017/?maxPoolSize=150} Error: { "serverUsed" : "127.0.0.1:27017" , "ok" : 0.0 , "errmsg" : "not authorized on admin to execute command { listDatabases: 1 }" , "code" : 13}
Pre-flight checks failed. Service can not start.

If there is a different MongoDB database running on 127.0.0.1:27017 that is not the application database (this can be possible for any reason, for example it could be the blockstore database), the result would be even worse: the Ops Manager application databases will be generated like on a fresh install on the wrong application database.

I believe that there should be a step between step 5 and step 6 that includes instruction on how to configure correctly the mongo.mongoUri parameter with the correct value before starting the mongodb-mms service from version 2.0 for the first time.

Kind regards,
Emilio