In this method, we simply export the database from the old release and import it in the new release. During this, the old database can be removed but it is best practice advise to keep the old release working on the old server just in case.

The steps for this method are simple:

1. Make a backup of the database or server (using mongodump)
2. Install the new software (preferably the latest)
3. Import the backup into the release (using mongorestore)

So let's get going:

As mentioned before, mongo has two types of backup:

• Physical
• Logical

In that method, we are using the LOGICAL one, as the physical will NOT be compatible with the new release.

[root@localhost backup]#  mongodump  --out /root/backup/`date +"%m-%d-%y"`
2019-09-16T06:31:47.226-0400    writing admin.system.version to
2019-09-16T06:31:47.227-0400    done dumping admin.system.version (1 document)
2019-09-16T06:31:47.227-0400    writing admin.artists to
2019-09-16T06:31:47.227-0400    done dumping admin.artists (2 documents)
[root@localhost backup]#

This command will export all not system databases and relations in the system.

After that install the new software, either on the same server: By deleting the old one and installing the new one OR on a new server.

[root@localhost ~]# yum install mongodb-org-server.x86_64
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: mirror.it4i.cz
 * extras: mirror.it4i.cz
 * updates: mirror.it4i.cz                                                                                                                                                                                                    | 2.5 kB  00:00:00
mongodb-org-4.2                                                                                                                                                                                                       | 2.5 kB  00:00:00
Resolving Dependencies
--> Running transaction check
---> Package mongodb-org-server.x86_64 0:4.2.14-1.el7 will be an update
--> Finished Dependency Resolution
 
Dependencies Resolved
 
=============================================================================================================================================================================================================================================
 Package                                                       Arch                                              Version                                                    Repository                                                  Size
=============================================================================================================================================================================================================================================
Updating:
 mongodb-org-server                                            x86_64                                            4.2.14-1.el7                                               mongodb-org-4.2                                             20 M
 
Transaction Summary
=============================================================================================================================================================================================================================================
Upgrade  1 Package
 
Total download size: 20 M
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
mongodb-org-server-4.2.14-1.el7.x86_64.rpm                                                                                                                                                                            |  20 MB  00:00:01
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Updating   : mongodb-org-server-4.2.14-1.el7.x86_64                                                                                                                                                                                    1/2                                                                                                                                                                               2/2
  Verifying  : mongodb-org-server-4.2.14-1.el7.x86_64                                                                                                                                                                                    1/2                                                                                                                                                                                2/2
 
Updated:
  mongodb-org-server.x86_64 0:4.2.14-1.el7
 
Complete!
[root@localhost ~]#

After that, we can simply import the exported data into the new release as follows:

[root@localhost]# mongorestore --host 172.27.1.245 -u adminDBA -p 'password' --port 27017  /root/backup/10-25-19/

connected to:172.27.1.245:27017
2018-03-20T17:43:50.660+0100 /root/backup/admin/artists.bson
2018-03-20T17:43:50.660+0100    going into namespace [admin.artists]
2018-03-20T17:43:50.682+0100
Creating index: { key: { _id: 1 }, name: "_id_", ns: "admin.artists" }
[root@lpara sales]