Upgrading a MongoDB replica set to 7.x on CentOS 8

Preparation

• Create a backup of the MongoDB databases
• Make a copy of the /etc/mongod.conf configuration file.
• If Passwork is installed on a virtual server, we recommend taking snapshots of the operating systems before performing the upgrade.
• Make sure the server has access to the MongoDB repositories.

The example uses three servers configured for data replication:

1. example-mongo-01 (PRIMARY)
2. example-mongo-02 (SECONDARY)
3. example-mongo-03 (SECONDARY)

Checking the current version

Check the MongoDB version in use:

shell

mongod --version

danger

If the MongoDB version is 4.2, you first need to upgrade to 4.4, because migration to MongoDB 5.0 is only available from version 4.4.

warning

If the current MongoDB version is already 4.4, go straight to the Upgrading the MongoDB replica set to version 5.0.x section.

Upgrading the MongoDB replica set to version 4.4

Adding the MongoDB repository

danger

The steps in this section must be performed on all servers of the replica set.

Create the repository file for MongoDB 4.4:

shell

nano /etc/yum.repos.d/mongodb-4.4.repo

Insert the contents:

shell

[mongodb-org-4.4]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/4.4/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-4.4.asc

Upgrading the MongoDB nodes

danger

The upgrade must be performed one instance at a time across the replica set.

Stop the MongoDB service:

shell

systemctl stop mongod.service

Upgrade MongoDB to version 4.4:

shell

dnf upgrade mongodb-org-tools mongodb-org-shell mongodb-org-server mongodb-org-database-tools-extra mongodb-org-database mongodb-org -y

danger

Do not update the MongoDB configuration file /etc/mongod.conf — keep the current version (N when prompted to replace it).

Start the MongoDB service:

shell

systemctl start mongod.service

Connect to the replica set and check the state of the nodes:

shell

mongo --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017
rs.status()

Changing the compatibility parameter

warning

featureCompatibilityVersion must be changed after all MongoDB instances have been upgraded.

Connect to the MongoDB shell (replica set):

shell

mongo --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017

Update the featureCompatibilityVersion parameter:

shell

db.adminCommand({ setFeatureCompatibilityVersion: "4.4" })

Open the Passwork web interface and make sure everything works correctly.

Upgrading the MongoDB replica set to version 5.0.x

Adding the MongoDB repository

danger

The steps in this section must be performed on all servers of the replica set.

Create the repository file for MongoDB 5.0.x:

shell

nano /etc/yum.repos.d/mongodb-5.0.repo

Add the contents:

shell

[mongodb-org-5.0]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/8/mongodb-org/5.0/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://pgp.mongodb.com/server-5.0.asc

Upgrading the MongoDB nodes

danger

The steps are performed one at a time on each node of the replica set.

Stop the MongoDB service:

shell

systemctl stop mongod.service

Upgrade MongoDB to version 5.0.x:

shell

dnf upgrade mongodb-org-tools mongodb-org-shell mongodb-org-server mongodb-org-database-tools-extra mongodb-org-database mongodb-org -y

danger

Do not update the MongoDB configuration file /etc/mongod.conf — keep the current version (N when prompted to replace it).

Start the MongoDB service:

shell

systemctl start mongod.service

Check the state of the replica set:

shell

mongo --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017
rs.status()

Changing the compatibility parameter

warning

Perform this after all nodes have been upgraded to version 5.0.x.

Connect to the MongoDB shell:

shell

mongo --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017

Update featureCompatibilityVersion:

shell

db.adminCommand({ setFeatureCompatibilityVersion: "5.0" })

Open the Passwork web interface and check that it works.

Upgrading the MongoDB replica set to version 6.0.x

Adding the MongoDB repository

danger

The steps in this section are performed on all servers of the replica set.

Create the repository file for MongoDB 6.0.x:

shell

nano /etc/yum.repos.d/mongodb-6.0.repo

Add the contents:

shell

[mongodb-org-6.0]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/8/mongodb-org/6.0/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://pgp.mongodb.com/server-6.0.asc

Upgrading the MongoDB nodes

danger

Perform the upgrade one node at a time across the replica set.

Stop the MongoDB service:

shell

systemctl stop mongod.service

Upgrade MongoDB to version 6.0.x:

shell

dnf upgrade mongodb-org-tools mongodb-org-shell mongodb-org-server mongodb-org-database-tools-extra mongodb-org-database mongodb-org -y

danger

Do not update the MongoDB configuration file /etc/mongod.conf — keep the current version (N when prompted to replace it).

Start the MongoDB service:

shell

systemctl start mongod.service

Check the state of the replica set:

shell

mongosh --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017
rs.status()

Changing the compatibility parameter

warning

Perform this after all nodes have been upgraded to version 6.0.x.

Connect to the MongoDB shell:

shell

mongosh --host rs0/example-mongo-01:27017,example-mongo-02:27017,example-mongo-03:27017

Update featureCompatibilityVersion:

shell

db.adminCommand({ setFeatureCompatibilityVersion: "6.0" })

Open the Passwork web interface and check that it works.

LLM version