@sgennadi Thanks for this, and for the detail. You were right: the check matched no_root_squash anywhere in /etc/exports, not just on the /images/dev export.
It is fixed now, much the way you proposed. The new nfsDevExportHasNoRootSquash() checks only the <share>/dev export. It ignores comments, other exports, and look-alike paths such as /images/dev2. Your ISO export with no_root_squash no longer triggers the warning.
Issue: https://github.com/FOGProject/fogproject/issues/1988 1.6 (working-1.6): https://github.com/FOGProject/fogproject/pull/1989 (merged) 1.6 RC: https://github.com/FOGProject/fogproject/pull/1990 (merged) 1.5 dev-branch: https://github.com/FOGProject/fogproject/pull/1991 (merged)To get it now, pull dev-branch (1.5) or rc-1.6.0 (1.6) and re-run the installer. It reaches the 1.5 stable branch with the monthly roll-up on November 11th.
The warning was only a message, so your exports were never changed. If /images/dev is already all_squash, you can ignore it until then.