# iSCSI on a Mac with Apple Silicon

> How to use iSCSI storage from a server or SAN on a Mac with Apple Silicon: macOS has no built-in iSCSI initiator, kernel-extension initiators need Reduced Security, and BeamDisk needs neither.

macOS doesn't include an iSCSI initiator, the software that connects a computer to iSCSI storage. Windows and Linux do. To use an iSCSI target on a storage server or SAN, a Mac needs a third-party initiator.

## The options on Apple Silicon

- **A kernel-extension initiator.** On a Mac with Apple Silicon, a kernel extension only loads after you restart into Recovery, lower the Mac's security policy to Reduced Security, approve the extension in System Settings and restart again, on every Mac.
- **A file share instead.** SMB or NFS gives the Mac a shared folder rather than a disk. It's not iSCSI, and the server keeps the file system.
- **BeamDisk.** A sandboxed Mac App Store app that connects to iSCSI targets with no kernel extension. The disk appears in Finder, Disk Utility and Time Machine like a local drive, and reads at over 1 GB/s on 10 GbE.

## What you need

- A Mac with Apple Silicon on macOS 27 or later.
- An iSCSI target with at least one disk (LUN). BeamDisk is tested with TrueNAS and with Linux targets (LIO / targetcli).
- The target must allow your Mac's initiator name, which BeamDisk shows in its window under This Mac.

## Set up BeamDisk

1. **Install BeamDisk** from the Mac App Store, and turn it on in System Settings when it asks.
2. **Allow your Mac on the target.** Copy the initiator name from BeamDisk (This Mac, or Settings → General) and add it to the target's allowed initiators on your server.
3. **Add Disk.** In BeamDisk, click Add Disk and enter your server's address, and its CHAP user and secret if it uses CHAP.
4. **Find Disks.** Click Find Disks, tick the disks you want and name them.
5. **Add them.** Click Add 1 Disk (or Add 2 Disks, and so on). The first time, click Connect All, then Allow… when BeamDisk asks to attach disks. The disks appear in Finder; format an empty one as APFS with Format… on its page.

The [full walkthrough](https://beamdisk.app/docs/getting-started/add-a-disk/) has every option.

## Frequently asked questions

### Does macOS have a built-in iSCSI initiator?

No. Windows and Linux include one, but macOS doesn't, so a Mac needs third-party software to use an iSCSI target.

### Can I use iSCSI on an M1, M2, M3 or M4 Mac?

Yes. BeamDisk runs on every Mac with Apple Silicon on macOS 27 or later, with no kernel extension.

### Do I need to lower my Mac's security to use iSCSI?

Not with BeamDisk. Kernel-extension initiators need Reduced Security on Apple Silicon; BeamDisk is a sandboxed Mac App Store app and leaves the Mac's security settings as they are.

### Is an iSCSI disk the same as a network share?

No. With SMB or NFS, the server manages the files and the Mac sees a shared folder. With iSCSI, the server provides a block device, the Mac formats it (APFS, for example), and it behaves like a disk plugged into the Mac. One Mac uses an iSCSI disk at a time.