After upgrading to macOS 27 “Golden Gate”, SymplyATOM2 may stop detecting your tape drive or fail to run certain operations. This article covers the two Golden Gate changes that cause this, and how to fix both in a few minutes.

TABLE OF CONTENTS

Overview

macOS 27 “Golden Gate” is a major system upgrade, not a minor point update, and major upgrades reset two things that SymplyATOM2 relies on. Neither is a bug in SymplyATOM2 - both are expected Apple behaviour on this kind of upgrade, and both are quick to put right.

  • Driver approval is reset. The ATTO ExpressSAS driver and macFUSE are disabled by the upgrade and macOS will not load them again until you re-approve them, exactly as if you had just installed SymplyATOM2 for the first time.
  • Rosetta 2 is removed. If Rosetta 2 was installed before the upgrade, Golden Gate removes it. SymplyATOM2 bundles a command-line tool called itdt, which is an Intel (x86_64) binary and needs Rosetta 2 to run - without it, operations that rely on itdt (Run Test, Host Validation, RMP reset, log retrieval, iSCSI reconnection) will fail.
Neither issue is destructiveNo data, settings, or tape catalogues are affected. Both fixes below just tell macOS to re-allow software it already trusted before the upgrade.

Issue 1 - Driver approval is reset

After the upgrade completes, SymplyATOM2 will not see your LTO tape drive because macOS has disabled the ATTO ExpressSAS driver and macFUSE. You will typically see a System Extension Blocked notification for one or both shortly after your Mac restarts into Golden Gate.

If you're familiar already with the process there's a minor change with macOS 27:

Boot into Recovery Mode (by holding the power button on Apple Silicon Macs), open Startup Security Utility, select Reduced Security, and enable "Allow user management of kernel extensions from identified developers".

The click-by-click approval steps are already documented in full, with screenshots, in our installation article - follow the same steps there again now, rather than a separate process:

Apple Silicon and the legacy KEXT path onlyIf you were still on the older kernel extension (KEXT) path for ATTO or macFUSE before upgrading (rather than the modern system extension used from macOS Tahoe onward), you may also need to re-enable Reduced Security in Recovery Mode - see Enable KEXT Driver Support - macOS. Most users upgrading from Tahoe are already on the modern driver and can skip this.

Issue 2 - Rosetta 2 is removed

SymplyATOM2 uses a bundled command-line tool called itdt to talk to your tape drive for several operations - Run Test, Host Validation, RMP reset, log retrieval, and iSCSI reconnection after a firmware update. itdt is still an Intel (x86_64) binary, so it needs Apple’s Rosetta 2 translation layer to run on Apple Silicon Macs. Golden Gate removes Rosetta 2 during the upgrade if it was previously installed, so any of these operations will fail or hang until it is reinstalled.

1
Open Finder › Applications › Utilities and double-click Terminal to open it.
2
Type the following command and press Return:
softwareupdate --install-rosetta --agree-to-license
3
Terminal will download and install Rosetta 2. This normally takes under a minute and does not require a restart.
4
Quit and reopen SymplyATOM2, then try the operation that was failing again (for example, Run Test).
You may see this happen automatically insteadmacOS sometimes offers to install Rosetta 2 itself the first time it encounters an Intel binary, showing a dialog with an Install button. If you see that prompt, click Install and you can skip the Terminal steps above.

Verify everything is working

1
Open SymplyATOM2 and confirm your LTO tape drive appears in the Drives panel.
2
Run a short Run Test or Host Validation to confirm itdt-backed operations complete without error.
Back to normalOnce the drive is detected and a test operation completes, both Golden Gate changes have been resolved and no further action is needed - these approvals persist through ordinary point updates.

Frequently asked questions

Do I need to do this after every macOS update?

No. Small point updates within Golden Gate (e.g. 27.0 to 27.1) do not reset driver approval or remove Rosetta 2. This only happens on a major version upgrade - moving from macOS 26 Tahoe to macOS 27 Golden Gate, or to whichever major version follows it.

Is any of this destructive to my tapes or catalogues?

No. Both issues are about macOS blocking previously-trusted software after a major upgrade - nothing on your tapes, in your SymplyATOM2 catalogue, or in your settings is touched.

How do I know if I’m affected by the Rosetta issue specifically?

If your tape drive appears in SymplyATOM2 but Run Test, Host Validation, an RMP reset, or log retrieval fails or hangs shortly after upgrading to Golden Gate, this is the most likely cause. Running the Terminal command in Issue 2 is safe to do even if Rosetta 2 turns out to already be installed - it will simply report that it is not needed.

My tape drive still doesn’t appear after following both fixes

Check the following in order:

  • Re-check System Settings › General › Login Items & Extensions (or Privacy & Security on the legacy KEXT path) to confirm both ATTO ExpressSAS and macFUSE show as approved, not blocked.
  • Restart your Mac - some approvals only take effect after a restart.
  • Confirm the ATTO ExpressSAS HBA and tape drive are correctly seated, connected, and powered on.

If the drive still does not appear after checking all of the above, submit a support ticket.

If you have any questions please submit a [support ticket]