Context

When setting up LangSmith in a production environment, you may want to use Azure Redis Enterprise with Active Geo replication. This requires understanding the specific Redis configuration requirements, including eviction policies, required modules, and authentication setup for LangSmith to work properly with Azure Redis Enterprise.

Answer

Yes, Azure Redis Enterprise is fully supported with LangSmith. Here's what you need to know for proper configuration:

Redis Eviction Policy

LangSmith requires the noeviction policy. This is because LangSmith uses Redis for:

• Queue management (using SAQ - Simple Async Queue for background job processing)

• Caching for temporary trace run data

All data stored in Redis has a configured TTL, so LangSmith relies on TTL-based expiration rather than eviction. Using noeviction prevents unexpected data loss during queue processing.

Important: With noeviction, if Redis reaches memory limits, write operations will return errors rather than silently evicting data. Ensure your Redis instance is appropriately sized for your workload.

Redis Modules

No additional modules are required. RediSearch and RedisJSON modules are not needed by LangSmith, as it uses standard Redis commands for queue operations and caching.

Azure Redis Enterprise Configuration

LangSmith has built-in support for Azure Cache for Redis with Entra ID (Azure AD) authentication. Configure it as follows:

redis:
  external:
    enabled: true
    connectionUrl: "rediss://<object-id>@<your-redis>.redis.cache.windows.net:6380"
    iamAuthProvider: "azure"

For Azure IAM authentication:

1. Include the Object ID of your managed identity or service principal as the username in the connection URL

2. Ensure your workload identity is properly configured so LangSmith services can obtain Azure AD tokens

Source: LangSmith Azure Self-Hosted Documentation