Hello jammac,

Which Isilon system do you have and what is your current onefs version?

The nodes are A200 if that is what u mean, and OneFs is 9.2.1

Hello jammac,

1. A domain mark is a mark on files and directories that are part of protection domains that prevents modifications. 
2. It can accelerate as it has to mark every file and directories.
3. It is recommended to run the Domain Mark job ahead before failing over or back to make the it faster.
4. In most cases it is worm as it is preventing modifications to files and directories.

Here is also a link to the web administrator guide. https://dl.dell.com/content/manual63960936-powerscale-onefs-9-2-1-0-web-administration-guide.pdf

Ok well that doesn't explain anything more than the manual.

Thanks anyway.