About Planmeca Romexis dental software
Planmeca Romexis is a comprehensive and versatile dental software platform developed by Planmeca, a leading manufacturer of dental equipment. It serves as an all-in-one solution that integrates various dental technologies and workflows into a single, user-friendly interface.
Key benefits of load balancing DPACS
Load balancing a dental PACS (Picture Archiving and Communication System) application is crucial for several reasons, primarily to ensure high availability, optimal performance, and the scalability of imaging data to ensure uninterrupted, high-quality patient care at volume.
For more on how load balancers solve key problems in healthcare, check out our eBook: Accelerating healthcare application delivery.
Why load balance DPACS with Loadbalancer.org?
We started our journey into the healthcare space over a decade ago by partnering with Carestream to provide high availability to their PACS system (HCIS). Since then we decided to focus on working with Enterprise imaging vendors by providing smart yet intuitive High Availability solutions to their mission critical applications. We realized that the most effective way to work with healthcare vendors was to create strategic-level partnerships to supply unbreakable, intuitive, and cost-effective load balancing solutions.
The key to our success is the flexibility of our approach. Whether it’s tailoring the user interface to the requirements of your application, branding the product to align with your go-to-market strategy, coming up with custom licensing agreements, or anything else that helps you – we’ve built a business model focused on flexibility for healthcare vendor partnerships. More on our healthcare expertise.
How to load balance Planmeca Romexis
The load balancer can be deployed in four fundamental ways: Layer 4 DR mode, Layer 4 NAT mode, Layer 4 SNAT mode, and Layer 7 SNAT mode.
For Planmeca Romexis, Layer 4 DR mode is recommended.
Virtual service (VIP) requirements
To provide load balancing and HA for Planmeca Romexis, the following VIP is required:
| VIP | Mode | Port(s) | Persistence mode |
|---|---|---|---|
| RomexisVIP | L4 DR | 104,1099,2099,50000-60000 | Source IP |
Deployment concept
Once the load balancer is deployed, clients connect to the Virtual Service (VIP) rather than connecting directly to a Planmeca Romexis server. These connections are then sent to the primary server if it’s up and passing health checks, and to the secondary server if not.
One-arm topology
One-arm direct routing (DR) mode is a very high performance solution that requires little change to your existing infrastructure. It provides full source IP address transparency and incredibly good performance.
When using a load balancer in one-arm DR mode all load balanced services can be configured on the same subnet as the real servers. The real servers must be configured to respond to the virtual server IP address as well as their own IP address. For more on one-arm topology see Topologies & Load Balancing Methods.
About Layer 4 DR mode
Layer 4 DR (Direct Routing) mode is a very high performance solution that requires little change to your existing infrastructure.
Note
Kemp, Brocade, Barracuda & A10 Networks call this Direct Server Return and F5 call it nPath.
The image below shows an example Layer 4 DR mode network diagram:
DR mode works by changing the destination MAC address of the incoming packet to match the selected Real Server on the fly which is very fast.
When the packet reaches the Real Server it expects the Real Server to own the Virtual Services IP address (VIP). This means that each Real Server (and the load balanced application) must respond to both the Real Server’s own IP address and the VIP.
The Real Server should not respond to ARP requests for the VIP. Only the load balancer should do this. Configuring the Real Server in this way is referred to as “Solving the ARP Problem”. For more information please refer to DR Mode Considerations.
On average, DR mode is 8 times quicker than NAT mode for HTTP and much faster for other applications such as Remote Desktop Services, streaming media and FTP.
The load balancer must have an interface in the same subnet as the Real Servers to ensure layer 2 connectivity which is required for DR mode to operate.
The VIP can be brought up on the same subnet as the Real Servers or on a different subnet provided that the load balancer has an interface in that subnet.
Port translation is not possible with DR mode, e.g. VIP:80 → RIP:8080 is not supported.
DR mode is transparent, i.e. the Real Server will see the source IP address of the client.