Configuring SEAL MongoDB¶

Hint - necessary configuration steps

Different database clients may require different configuration steps, see overview.

Hint - replica set required

MongoDB requires a replica set for both, single server and server cluster.

Configuring a Shared Replica Set¶

Caution - cluster

In a cluster, all servers must use the same database. Therefore you have to perform the following configuration steps on every member of the replica set separately.

In an editor, open the MongoDB configuration file:
```
/opt/seal/etc/mongod.conf
```
Check whether the bindIp property exists and contains the following value:
```
bindIp: 0.0.0.0
```
Check whether the replication section exists, and contains the following properties:
```
replication:
  oplogSizeMB: 2048
  replSetName: seal
```
Hint - oplogSizeMB

We recommend setting oplogSizeMB to 5 % of the disk space available for MongoDB.

Caution - replSetName identical on all servers

If you change the default of replSetName, make sure you change it to the same value on all servers.
Restart MongoDB:
```
sudo systemctl restart mongod
```

Initializing the Database¶

Caution - replica set primary only

Perform the following configuration step only on the replica set primary.

Initialize the cluster on <server_1>:

sudo mongosh --tls --tlsAllowInvalidCertificates --eval "rs.initiate({ _id : 'seal', members: [{ _id : 0, host : '<server_1>' }]})"

The output has to contain the following line:

"ok" : 1

Connecting the Database Servers to the Cluster¶

After initializing the database cluster on the replica set primary, add the other members of the replica set.

Caution - replica set primary only

Perform the following configuration step on the replica set primary only.

Add <server_2> to the cluster:
```
sudo mongosh --tls --tlsAllowInvalidCertificates --eval "rs.add('<server_2>')"
```
The output has to contain the following line::

"ok" : 1
Add <server_3> to the cluster:
```
sudo mongosh --tls --tlsAllowInvalidCertificates --eval "rs.add('<server_3>')"
```
The output has to contain the following line::

"ok" : 1
Proceed until all servers are added.

Proceed with Securing MongoDB: TLS encryption or user authentication.