Enable encryption in transit
Enable encryption (using TLS) for client- and server-server communication
      Prerequisites
Before you can enable and use server-to-server (inter node) and client-to-server encryption, you need to create and configure server certificates for each node of your YugabyteDB cluster. For information, see Create server certificates.
Configure YB-Master and YB-TServer nodes
To enable server-to-server and client-to-server TLS encryption, start your YB-Master and YB-TServer nodes using the following flags.
| Configuration flag | Description | 
|---|---|
| use_node_to_node_encryption | Set to trueto enable encryption between YugabyteDB nodes. Default isfalse. | 
| use_client_to_server_encryption | Set to trueto enable encryption between clients and the database cluster. Default isfalse. | 
| allow_insecure_connections | Set to falseto disallow any service with unencrypted communication from joining this cluster. Default istrue. Note that this flag requires--use_node_to_node_encryptionor--use_client_to_server_encryptionto be enabled. | 
| certs_dir | Optional. Directory containing the certificates created for this node to perform encrypted communication with the other nodes. Default for YB-Masters is <data drive>/yb-data/master/data/certsand for YB-TServers is<data drive>/yb-data/tserver/data/certs. | 
| certs_for_client_dir | Optional. Directory containing the configuration for the client to perform TLS communication with the cluster. Defaults to the same directory as the node-to-node encryption (certs_dir). | 
Start the YB-Masters
You can enable encryption in transit by starting the yb-master services with the following flags:
bin/yb-master                               \
    --fs_data_dirs=<data directories>       \
    --master_addresses=<master addresses>   \
    --certs_dir=/home/centos/tls/$NODE_IP   \
    --allow_insecure_connections=false      \
    --use_node_to_node_encryption=true      \
    --use_client_to_server_encryption=true
For information on starting YB-Master nodes for a deployment, see Start YB-Masters.
Start the YB-TServers
You can enable encryption in transit by starting the yb-tserver services with the following flags:
bin/yb-tserver                                  \
    --fs_data_dirs=<data directories>           \
    --tserver_master_addrs=<master addresses>   \
    --certs_dir /home/centos/tls/$NODE_IP       \
    --allow_insecure_connections=false          \
    --use_node_to_node_encryption=true          \
    --use_client_to_server_encryption=true
For information on starting YB-TServers for a deployment, see start YB-TServers.