Tech Specs

Technical Information

Operating system

OttoFMS will run on any operating system that is certified to run FileMaker Server 19.6 or greater, including the newly released FileMaker Server 21.0

FileMaker Server version

FileMaker Server version 19.6 or greater is required. OttoFMS will not work with FileMaker Server 19.5 or earlier.

Claris support

FileMaker Server 19.6 is currently supported by Claris. However, on Dec 31, 2024 Claris will end support for FileMaker Server 19. We will not do anything to prevent you from using OttoFMS with FileMaker Server 19.6 after that date, but we will prioritize support for the Claris-supported versions of FileMaker Server.

You can check the current schedule for End of Life dates for FileMaker Server on the Claris website (opens in a new tab).

Minimum requirements

OttoFMS' minimum requirements for a server are:

  • 4 CPU cores
  • 8GB RAM
  • Available virtual memory or swap file.

Migrations make copies of your database files both in RAM and on disk as part of the migration process. A good general rule is that if you need to have 3x the size of your production database files in available disk space, and at least 2x the size of your production database files in RAM or virtual memory.

Bigger is better.

Builds and migration will be faster with more CPU cores and more RAM. Each file migration consumes 2.5 Gb of RAM and a significant amount of CPU. If you want to run concurent migrations, you will need more CPU and RAM.

Burst-able instances are not recommended


Burst-able Instances Should be Avoided.
They are not suitable for hosting FileMaker Server with or without OttoFMS. Do not use them.

It will causes services to be throttled when the server is under load. This can cause FileMaker Server to be unresponsive and can cause migrations and other OttoFMS operations to appear to stall out. A single file migration may cause a burst-able instance to throttle, and it may remain throttled for hours.

AWS T-Types are a common example of burst-able instances. Don't use them.

Virtual memory

Mac and Windows have virtual memory. They can use available disk space as RAM as needed. This does slow down the server. You can read more about virtual memory at Wikipedia (opens in a new tab).

Linux swap files

Linux may or may not have a swap file by default. We recommend that you don't install OttoFMS on a Linux production server without a swap file configured.