# 2026.04 Infrastructure Changes

## Changes on Application environment

| **Change** | **Name** | **Application Default Value**<br>**(if env variable unset)** | **Example** | **Required** | **Applications** | **Short Description** |
| --- | --- | --- | --- | --- | --- | --- |
| Removed | `FEATURE_FLAG_NEW_SOURCE_REFERENCES_UN_10906` | - | - | - | - `web-app-chat` | Enabled new UI for source references in chat.<br>Can be removed since it is GA now. |
| Added | `FEATURE_FLAG_ENABLE_SESSION_TIMEOUT_UN_15656` | `false` | `true` | false | - `web-app-knowledge-upload`<br>  <br>- `web-app-chat`<br>  <br>- `web-app-theme`<br>  <br>- `web-app-admin` | Enables automatic log out of users after 30 minutes of inactivity. |
| Added | `PUBSUB_REDIS_CLUSTER_MODE` | `false` | `true` | false | - `backend-service-chat` | Enables Redis cluster mode for `backend-service-chat`<br>(see below) |
| Added | `PUBSUB_REDIS_CLUSTER_NODES` | unset | ```<br>[<br>{"host":"localhost","port":10130},<br>{"host":"localhost","port":10131}<br>]<br>``` | false | - `backend-service-chat` | A JSON list of Redis Cluster nodes (host & port) |
| Added | `PUBSUB_REDIS_USERNAME` | unset | `default` | false | - `backend-service-chat` | Allows providing username to authenticate the Redis connection |
| Added | `PUBSUB_REDIS_CLUSTER_USERNAME` | unset | `default` | false | - `backend-service-chat` | Configures the username to use to connect to the Redis Cluster |
| Added | `PUBSUB_REDIS_CLUSTER_PASSWORD` | unset | `secret-password` | false | - `backend-service-chat` | Configures the password to use to connect to the Redis Cluster |
| Added | `PUBSUB_REDIS_CLUSTER_ENABLE_TLS` | `false` | `true` | false | - `backend-service-chat` | Whether to configure the connection with TLS support. Only when using TLS Redis. For cluster mode ONLY. |
| Added | `PUBSUB_REDIS_TLS_REJECT_UNAUTHORIZED` | `true` | `false` | false | - `backend-service-chat` | Whether to reject unverified or self-signed CA, when using Redis with TLS |

## Migration command changes

As from release 2026.04, a config parameter (`--config ../prisma.config.ts`) must be added when running the Prisma database migrations. Other migration commands are not affected do not need to be adjusted, only the Prisma part.

The easiest way to perform this change is to search and replace the following lines:

```
// search for
npx prisma migrate deploy;

// replace with
npx prisma migrate deploy --config ../prisma.config.ts;
```

The Prisma migration part must be adjusted in all backend services that are running migrations:

- `backend-service-app-repository`

```
cd /home/node/app/services/node-app-repository/prisma; npx prisma migrate deploy --config ../prisma.config.ts;
```

- `backend-service-chat`

```
cd /home/node/app/services/node-chat/prisma; npx prisma migrate deploy --config ../prisma.config.ts;
```

- `backend-service-configuration`

```
cd /home/node/app/services/configuration-backend/prisma; npx prisma migrate deploy --config ../prisma.config.ts;
```

- `backend-service-ingestion`

```
cd /home/node/app/services/node-ingestion/prisma; npx prisma migrate deploy --config ../prisma.config.ts;
```

- `backend-service-scope-management`

```
cd /home/node/app/services/node-scope-management/prisma; npx prisma migrate deploy --config ../prisma.config.ts;
```

## Redis Cluster and ACL Support

Optional - Only enable this if you have a requirement to run Redis in Cluster mode.

Release **2026.04** now supports Redis Cluster mode. To make use of the Redis Cluster mode, set the `PUBSUB_REDIS_CLUSTER_MODE` variable to `true` and provide the cluster nodes in `PUBSUB_REDIS_CLUSTER_NODES` as a JSON array of objects with the corresponding host and port of each nodes in the cluster.

[Redis ACL auth](https://redis.io/docs/latest/operate/oss_and_stack/management/security/acl/) (username + password) for both standalone and cluster mode is now supported in the `backend-service-chat` service given that the environment variables `PUBSUB_REDIS_USERNAME` and `PUBSUB_REDIS_PASSWORD` are provided **when using Redis standalone**, and `PUBSUB_REDIS_CLUSTER_USERNAME` and `PUBSUB_REDIS_CLUSTER_PASSWORD` are provided **when using Redis Cluster mode**.

**Note:** All of these variables are not required and the existing configurations continue to work. So if you do not need ACL authentication and/or cluster mode, everything should work as it used to. However, if you turn on cluster mode then it’s required that cluster nodes are set. Cluster settings do not interfere with regular settings even when both are present, and a switch can easily be made between cluster settings and regular settings by only setting `PUBSUB_REDIS_CLUSTER_MODE` to either `true` or `false`.

| **Author** | Solution Engineering |