Charmed MongoDB 6 Tutorial - Enable security

Enable Security in your MongoDB deployment

This is part of the Charmed MongoDB Tutorial. Please refer to this page for more information and the overview of the content.

Transport Layer Security (TLS)

TLS is used to encrypt data exchanged between two applications; it secures data transmitted over the network. Typically, enabling TLS within a highly available database, and between a highly available database and client/server applications, requires domain-specific knowledge and a high level of expertise. Fortunately, the domain-specific knowledge has been encoded into Charmed MongoDB K8S. This means enabling TLS on Charmed MongoDB K8S is readily available and requires minimal effort on your end.

Again, relations come in handy here as TLS is enabled via relations; i.e. by relating Charmed MongoDB K8s to the Self Signed Certificates Charm. The Self Signed Certificates Charm centralises self-signed certificate management in a consistent manner and handles providing, requesting, and renewing self-signed TLS certificates.

Note: Only for the tutorial sake we will use self-signed certificates provided by self-signed-certificates-operator. For production environments you should use tls-certificates-operator.

Configure TLS

Before enabling TLS on Charmed MongoDB K8s we must first deploy the tls-certificates-operator charm:

juju deploy self-signed-certificates --channel=beta

Wait until the self-signed-certificates is ready to be configured. When it is ready to be configured juju status --watch 1s. Will show:

Model     Controller  Cloud/Region         Version  SLA          Timestamp
tutorial  overlord    localhost/localhost  3.1.6   unsupported  09:24:12Z

App                        Version  Status   Scale  Charm                      Channel   Rev  Exposed  Message
mongodb                             active       2  mongodb                    6/beta   140  no       Replica set primary
self-signed-certificates            active       1  self-signed-certificates   beta       33  no     

Unit                          Workload  Agent  Machine  Public address  Ports      Message
mongodb/0*                    active    idle   0    27017/tcp  Replica set primary
mongodb/1                     active    idle   1     27017/tcp  Replica set secondary
self-signed-certificates/0*   active    idle   3                 

Machine  State    Address       Inst id        Series  AZ  Message
0        started  juju-d35d30-0  jammy       Running
1        started   juju-d35d30-1  jammy       Running
3        started    juju-d35d30-3  jammy       Running

Enable TLS

After configuring the certificates watch -n 1 juju status will show the status of self-signed-certificates as active. To enable TLS on Charmed MongoDB K8s, relate the two applications:

juju integrate mongodb self-signed-certificates

Connect to MongoDB with TLS

Like before, generate and save the URI that is used to connect to MongoDB:

echo $URI

Now ssh into mongodb/0:

juju ssh mongodb/0

After sshing into mongodb/0, we are now in the unit that is hosting Charmed MongoDB. Once TLS has been enabled we will need to change how we connect to MongoDB. Specifically we will need to specify the TLS CA file along with the TLS Certificate file. These are on the units hosting the Charmed MongoDB application in the folder /var/snap/charmed-mongodb/common/etc/mongod. If you enter: ls /var/snap/charmed-mongodb/current/etc/mongod/external* you should see the external certificate file and the external CA file:

/var/snap/charmed-mongodb/current/etc/mongod/external-ca.crt  /var/snap/charmed-mongodb/current/etc/mongod/external-cert.pem

As before, we will connect to MongoDB via the saved MongoDB URI. Connect using the saved URI and the following TLS options:

sudo charmed-mongodb.mongosh mongodb://$DB_USERNAME:$DB_PASSWORD@$HOST_IP/$DB_NAME?replicaSet=$REPL_SET_NAME --tls --tlsCAFile /var/snap/charmed-mongodb/current/etc/mongod/external-ca.crt  --tlsCertificateKeyFile /var/snap/charmed-mongodb/current/etc/mongod/external-cert.pem

Congratulations, you’ve now connected to MongoDB with TLS. Now exit the MongoDB shell by typing:


Now you should be back in the host of Charmed MongoDB (mongodb/0). To exit this host type:


You should now be shell you started in where you can interact with Juju and LXD.

Disable TLS

To disable TLS unrelate the two applications:

juju remove-relation mongodb-k8s self-signed-certificates

Next step

Charmed MongoDB Tutorial - Environment Cleanup