=====Overview=====
In this section we will upgrade 4.0 to 4.2. For that we have to disable the monitoring during the upgrade.
From 4.2 we can upgrade to 4.3 without downtime, but since it is 4.0 we need downtime.

https://docs.opsmanager.mongodb.com/current/tutorial/upgrade-ops-manager/

=====Preparation=====
We have to prepare first, as so:

  * Backup the config files
  * Upload the new Software

Of course we need the backup the old configuration before changing anything.

====Backup Config files====
Be sure to configure the following directories:

  * <install_dir>/conf
  * <install_dir>/logs

That will provide you the configuration files and the log files.
You can backup the whole directory as follows:

<Code:bash|Check where Mongo is installed>
[root@dbpafxjrl ~]# rpm -qa | grep -i mongo
mongodb-mms-automation-agent-manager-5.4.17.5525-1.x86_64
mongodb-enterprise-server-4.0.6-1.el7.x86_64
mongodb-enterprise-mongos-4.0.6-1.el7.x86_64
mongodb-enterprise-tools-4.0.6-1.el7.x86_64
mongodb-mms-4.0.9.50422.20190307T1523Z-1.x86_64
mongodb-enterprise-shell-4.0.6-1.el7.x86_64
[root@dbpafxjrl ~]# rpm -ql mongodb-mms-4.0.9.50422.20190307T1523Z-1.x86_64
/opt/mongodb/mms
</Code>

We see that Mongo is installed from RPM in: "/opt/mongodb/mms"

Let's backup the whole folder:

<Code:Backup the installation folder>
[root@dbpafxjrl mongodb]# tar cvf /data/backup/mms.backup.tar /opt/mongodb/mms/
mms/
mms/MMS-MONGODB-MIB.txt
mms/README
mms/THIRD-PARTY-NOTICES
mms/VERSION
mms/agent/
mms/agent/automation/
******************************************
</Code>

Once we have a backup, let's continue with the upgrade

====Upload the new binaries====
The binaries can be downloaded from the link above or from [[https://www.mongodb.com/try/download/ops-manager||here.]]
After you download the RPM, upload it to the software location on the server where you want to install it.

=====Upgrade=====
====Stop the MongoOps manager====
We have to stop the MongoOps manager as follows:

<Code:bash|Stop MongoOps>
[root@dbpafxjrl ~]# /opt/mongodb/mms/bin/mongodb-mms stop
Stop Ops Manager server
   Instance 0 stopping
      Trying graceful shutdown..[  OK  ]
Stop Backup Daemon.........[  OK  ]
[root@dbpafxjrl ~]#
</Code>

====Upgrade the RPM====
We can install the RPM as follows:

<Code:bash|Check for dependencies & Upgrade RPM>
[root@dbpafxjrl ~]# rpm -Uvh --test mongodb-mms-4.2.14.56911.20200603T2241Z-1.x86_64.rpm
Preparing...                          ################################# [100%]
[root@dbpafxjrl ~]# rpm -Uvh mongodb-mms-4.2.14.56911.20200603T2241Z-1.x86_64.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:mongodb-mms-4.2.14.56911.20200603################################# [ 50%]
Cleaning up / removing...
   2:mongodb-mms-4.0.9.50422.20190307T################################# [100%]
[root@dbpafxjrl ~]#
</Code>

====Start MongoOps====
Once we are done, we can start it again:

<Code:bash|Start MongoOps>
[root@dbpafxjrl conf]# /opt/mongodb/mms/bin/mongodb-mms start
Starting pre-flight checks
Successfully finished pre-flight checks

Migrate Ops Manager data
   Running migrations...[  OK  ]
Starting Ops Manager server
   Instance 0 starting...................[  OK  ]
Starting pre-flight checks
Successfully finished pre-flight checks

Start Backup Daemon...[  OK  ]
[root@dbpafxjrl conf]#
</Code>