This article is valid for Digital Access 6.2 and later.

This article describes how to run Smart ID Digital Access component in distributed mode.

Distributed mode is used when the different functions in Digital Access component are distributed to several virtual appliances. A typical case is when you want to enforce the access in one appliance (PEP, Policy Enforcement Point) and process the authorization and authentication requests in one appliance (PDP, Policy Decision Point). In this case you will need two appliances. One that runs access point and another that runs the other Digital Access component services.

Administration service limitations

There can be only one administration service in a node network. Nodes running other services should be connected to the administration service node. Once a service has successfully connected to an administration service, then that service cannot easily be switched to work with another appliance's administration service.

Manager node is the node that hosts the administration service.
Worker node is a node that hosts other services, not running the administration service.
Make sure 1003 is available for user id and group id.

Prerequisites

Two Digital Access components with services and docker swarm available
The following ports shall be open to traffic to and from each Docker host participating on an overlay network:
- TCP port 2377 for cluster management communications
- TCP and UDP port 7946 for communication among nodes
- UDP port 4789 for overlay network traffic
For more details refer to: https://docs.docker.com/network/overlay/
Keep a note of IP addresses of nodes where access point is running.

Step-by-step instruction

Get token and stop services - manager node

Get cluster join token

SSH to the node running the administration service, that is, the manager node.
Get the cluster join token by running this command. This token will be used for joining worker nodes to the manager node.

Get token

sudo docker swarm join-token worker

The output of the command will be like:

Output

docker swarm join --token SWMTKN-1-5dxny21y4oslz87lqjzz4wj2wejy6vicjtqwq33mvqqni42ki2-1gvl9xiqcrlxuxoafesxampwq 192.168.253.139:2377

Stop services

Stop the running services.

Stop services

sudo docker stack rm <your da stack name>

Join as worker nodes

See Join as worker nodes in Set up high availability for Digital Access component.

At manager node

Remove labels, verify and identify nodes

SSH to manager node.
Remove label for all services which are not required on this node.
Remove label
```
sudo docker node update --label-rm  da-access-point <nodeid>
```
Verify if all nodes are part of cluster by running this command.
Verify if all nodes are part of cluster
```
sudo docker node ls
```
Identify nodes ID, master and worker where the service will be distributed.
Identify nodes
```
sudo docker node inspect --format '{{ .Status }}' h9u7iiifi6sr85zyszu8xo54l
```
Output: {ready 192.168.86.129} - IP address will help to identify the DA node

Update labels for each service

Update labels for each service which you want to run on worker nodes.

<node ID> is the id of the node on which the service will be running.

Commands to update labels

sudo docker node update --label-add da-policy-service=true <worker node ID>
sudo docker node update --label-add da-access-point=true <worker node ID>

Deploy your stack using this command. To run the command your working directory should be docker-compose.
Deploy DA stack
```
sudo docker stack deploy --compose-file docker-compose.yml -c network.yml -c versiontag.yml <your da stack name>
```

docker stack deploy is the command to deploy services as stack.
compose file flag is used to provide the file name of base docker-compose file.
-c is short for –compose-file flag. It is used to provide override files for docker -compose.
<your da stack name> is the name of the stack. You can change it based on requirements.

Run Digital Access component in distributed mode