For an on-premises solution, you can follow these steps:

1. Database Configuration Ensure both servers point to the same on-premises database.

2. Shared File Storage Use a shared network file share (NFS or SMB) for media files.

3. Distributed Caching Use an on-premises distributed caching solution like Redis.

4. Logging Centralize your logging using an on-premises ELK stack (Elasticsearch, Logstash, and Kibana).

5. Load Balancing Use a hardware or software load balancer to distribute traffic between the two servers.

Detailed Configuration 1. Database Configuration Ensure your connection string in appsettings.json points to a single shared database:

"Umbraco": {
  "CMS": {
    "Global": {
      "UmbracoDbDSN": "Server=your_onprem_server;Database=your_database;User Id=your_username;Password=your_password;"
    }
  }
}

1. Shared File Storage Configure Umbraco to use a shared network file system.

Configure appsettings.json:

"Umbraco": {
  "CMS": {
    "Content": {
      "Media": {
        "FileSystem": {
          "Provider": "Physical",
          "RootPath": "\\\\your_network_share\\media",
          "RootUrl": "/media"
        }
      }
    }
  }
}

1. Distributed Caching Set up Redis on-premises.

Install the Redis package:

dotnet add package Microsoft.Extensions.Caching.StackExchangeRedis
Configure 

appsettings.json:

"Umbraco": {
  "CMS": {
    "Caching": {
      "DistributedCache": {
        "Enabled": true,
        "Provider": "Redis",
        "Redis": {
          "Configuration": "your_redis_server:6379"
        }
      }
    }
  }
}

1. Logging Set up an on-premises ELK stack and configure logging.

Configure appsettings.json:

"Logging": {
  "LogLevel": {
    "Default": "Information",
    "Microsoft": "Warning",
    "Microsoft.Hosting.Lifetime": "Information"
  },
  "Elasticsearch": {
    "Uri": "http://your_elasticsearch_server:9200",
    "IndexFormat": "logs-{0:yyyy.MM.dd}",
    "TemplateName": "logs",
    "TemplateMatch": "logs-*"
  }
}

1. Load Balancing Set up a load balancer to distribute traffic between the two servers. This can be a hardware load balancer or a software solution like HAProxy or Nginx.

Summary

Database: Point both servers to the same on-premises database. Media Storage: Use a shared network file share.

Distributed Caching: Set up Redis on-premises for shared caching. Logging: Use an on-premises ELK stack for centralized logging.

Load Balancing: Implement load balancing with a hardware or software solution.

This setup will ensure both servers share caching, logging, and media, providing a high-availability environment on-premises.

Please verify and suggest if there any better approach available.?