Fast iSCSI for Macs with Apple Silicon

BeamDisk is the first high-performance iSCSI initiator for Apple Silicon. Connect to your storage server or SAN, and its disks appear in Finder and Time Machine like local drives. No kernel extension, no Recovery-mode restarts, no lowered security.

  • Free for home use
  • No kernel extension
  • macOS 27 or later on Apple Silicon
Benchmarks

Measured, not promised.

Real runs on a Mac and a server over 10 GbE, replayed second by second. Every run lists what it ran on, and the method is published.

Runs

Sequential read and write

Separate 180 s write and read runs, replayed one after the other at 12×

Reads and writes, each measured on its own, both run at over 99% of what 10 GbE can carry.

Results

SustainedPeak
Read1,230 MB/s1,237 MB/s
Write1,236 MB/s1,237 MB/s

What it ran on

Mac
Apple M4, 16 GB
macOS
27.0.1
BeamDisk
1.0 (development build)
Storage
Linux LIO iSCSI target on Debian 13, SATA SSDs
Network
10GBase-T, MTU 9000, one session
Test
1 MiB blocks, 8 in flight, 8 GiB file on APFS; reads and writes in separate 180 s runs
Date
October 25, 2026

Random read and write

Separate 180 s write and read runs, replayed one after the other at 12×

Random 16 KiB reads and writes, each measured on its own, at the memory page size of Macs with Apple Silicon.

Results

SustainedPeak
Read20.2K IOPS20.6K IOPS
Write24.0K IOPS24.4K IOPS

What it ran on

Mac
Apple M4, 16 GB
macOS
27.0.1
BeamDisk
1.0 (development build)
Storage
Linux LIO iSCSI target on Debian 13, SATA SSDs
Network
10GBase-T, MTU 9000, one session
Test
16 KiB blocks, 16 in flight for writes and 48 for reads, 2 GiB file on APFS; reads and writes in separate 180 s runs
Date
October 25, 2026

Mixed sequential

180 s of reads and writes at once, replayed at 6×

Reading and writing at the same time, BeamDisk moved 1,844 MB/s in all, about 1.5 times what one direction of 10 GbE can carry; reads took the larger share.

Results

SustainedPeak
Together1,844 MB/s1,928 MB/s
Read1,154 MB/s1,210 MB/s
Write690 MB/s725 MB/s

What it ran on

Mac
Apple M4, 16 GB
macOS
27.0.1
BeamDisk
1.0 (development build)
Storage
Linux LIO iSCSI target on Debian 13, SATA SSDs
Network
10GBase-T, MTU 9000, one session
Test
1 MiB blocks, 8 reads and 8 writes in flight at once, 8 GiB file on APFS, 180 s
Date
October 26, 2026

Mixed random, 70/30

180 s of reads and writes at once, replayed at 6×

A 70/30 mix of random 16 KiB reads and writes at the same time ran at 26.2K operations a second in all, more than either direction alone.

Results

SustainedPeak
Together26.2K IOPS26.7K IOPS
Read18.3K IOPS18.8K IOPS
Write7.8K IOPS8.1K IOPS

What it ran on

Mac
Apple M4, 16 GB
macOS
27.0.1
BeamDisk
1.0 (development build)
Storage
Linux LIO iSCSI target on Debian 13, SATA SSDs
Network
10GBase-T, MTU 9000, one session
Test
16 KiB blocks at random offsets, 70% reads, 32 in flight, 2 GiB file on APFS, 180 s
Date
October 26, 2026

Time Machine: iSCSI vs SMB

Both backups, replayed at 60×

The same first full backup of a Mac (71.4 GB, 1.8 million files) to the same SSD pool took 8 min 19 s over BeamDisk and 9 min 39 s over SMB: 14% less time.

Results

AveragePeakFinished in
BeamDisk (iSCSI)143 MB/s391 MB/s8 min 19 s
SMB123 MB/s355 MB/s9 min 39 s

What it ran on

Mac
Apple M4, 16 GB
macOS
27.0.1
BeamDisk
1.0 (development build)
Storage
TrueNAS, SATA SSD pool, no SLOG
Network
10GBase-T, MTU 9000, one session
Test
First full backup of the same Mac (71.4 GB of Time Machine's data, 1,815,793 files), minutes apart: to an empty BeamDisk disk, then to a new Time Machine share over SMB, both on the same pool
Date
October 22, 2026

Your results depend on your server, its disks and your network. BeamDisk's built-in Test Speed measures your own setup in about a minute.

No kernel extension

Installs like an app. Because it is one.

Kernel-extension initiators ask a lot of a Mac with Apple Silicon. BeamDisk asks for one switch.

The kernel-extension way

Recovery, Reduced Security, two restarts. On every Mac.

  1. Shut down, then press and hold the power button and choose Options to start up in Recovery.

  2. Open Startup Security Utility and lower the Mac's security policy to Reduced Security, allowing kernel extensions from identified developers.

  3. Restart, install the software, and allow its kernel extension in System Settings → Privacy & Security.

  4. Restart again. Then repeat on every Mac.

The BeamDisk way

One switch. No restart. Security unchanged.

  1. Install BeamDisk from the Mac App Store.

  2. Turn BeamDisk on in System Settings when it asks. Once.

  3. Add your disks. No restart, and your Mac's security settings stay exactly as they were.

  • A sandboxed Mac App Store app.
  • Nothing to allow-list in your MDM's kernel-extension policy.
  • Nothing left behind in the system when you delete it.
Features

Everything a disk should do.

The BeamDisk window: throughput, IOPS and latency for every disk, graphs kept for 7 days, and each disk's state in plain words. Here Projects reads at 1,230 MB/s, the rate sustained over 180 s on 10 GbE.
  • Live in the menu bar

    Throughput and IOPS right in the menu bar, split by read and write if you like, in MB/s, MiB/s or Gb/s. Graphs with p50 and p99 latency, kept for 7 days.

  • CHAP and mutual CHAP

    Authenticate to the server, and have the server prove itself too. Secrets live in your Keychain, on this Mac only.

  • Rides out outages

    If the server stops answering, BeamDisk holds writes for up to 60 seconds (you choose 15 to 300) and reconnects by itself. Apps carry on as if nothing happened.

  • One Mac at a time, enforced

    BeamDisk takes exclusive access to each disk, so a second computer can't write to it and corrupt it. It keeps that hold through reconnects.

  • Keeps working when you quit

    Disks stay connected when you quit the app, unless you choose to disconnect them. Connect at login, disk by disk.

  • Finds your disks

    Enter your server's address and BeamDisk lists every disk it offers this Mac, with its size. Tick the ones you want and name them.

  • Time Machine to your server

    Use an iSCSI disk as a Time Machine destination, after a one-time setup in BeamDisk's settings.

  • Test Speed, built in

    Eight tests in about a minute, reading and writing files as apps do: sequential and random, reads and writes, latency and synced writes. Test files are removed afterwards.

  • Gives space back

    Delete files on an APFS disk and BeamDisk returns the free space to your server: when the disk connects, or whenever you click Reclaim Free Space.

  • Formats in a click

    A blank disk gets an APFS format tuned for network storage, or use Disk Utility for anything else.

  • Tells you what happened, and when

    Notifications when the server stops responding, when a disk reconnects, or when another computer takes a disk. In the app, every message and every problem says when it happened.

  • CRC32C digests

    Optional header and data checksums on every command, when your target supports them.

APFS and Mac OS Extended (Journaled) read and write. exFAT, FAT and NTFS disks attach read-only.

For IT and fleets

Easy to approve. Easy to deploy.

Every disk state has one glyph, one plain label and at most one thing to do.
  • No kernel extension to approve

    No Reduced Security, no Recovery-mode visits, no kernel-extension policy. The Mac keeps the security your MDM enforces.

  • A sandboxed Mac App Store app

    Apple reviews and signs every release, and updates come through the App Store.

  • Volume purchase

    A separate BeamDisk app for organizations, $25 per Mac, bought in volume through Apple Business Manager and assigned by your MDM like any App Store app.

  • Licensing procurement understands

    Business use needs a license after the trial, one per Mac, bought in the app or in volume. The terms are on the pricing page, in plain words.

  • Data safety you can explain

    Exclusive access stops two Macs writing one disk, flushes reach the server, brief outages are ridden out, and every state is visible.

  • No account, no analytics

    BeamDisk connects only to your storage, and to Apple for purchases and updates.

BeamDisk for business

For homelabs

Built for the server in your closet, too.

  • Free for home use, forever

    Personal, non-commercial use stays free after the trial, with one server and up to 2 disks.

  • Bring your server

    BeamDisk speaks standard iSCSI. It's tested with TrueNAS and with Linux targets (LIO / targetcli).

  • Time Machine over iSCSI

    Back up to your server as if it were a disk on your desk.

  • See your network's real speed

    Test Speed shows what your server and network can do.

Test Speed on 10 GbE to a Linux iSCSI target: 1,225 MB/s sequential write, 1,152 MB/s sequential read, about 19.5K random 16 KiB reads and 17.7K writes per second, and 0.45 ms read latency.
Set up

Three steps to a network disk.

  1. Install

    Get BeamDisk from the Mac App Store, and turn it on in System Settings when it asks.

  2. Add Disk

    Enter your server's address, and its CHAP secret if it uses one. Pick your disks.

  3. Use it

    The disk appears in Finder. Format a blank one as APFS in a click.

    Add your first disk, step by step

Compatibility

What you need.

A Mac with Apple Silicon on macOS 27 or later, and an iSCSI target on a storage server or SAN (tested with TrueNAS). Wired Ethernet is recommended.

MacApple Silicon (M1 or later)
macOSmacOS 27 or later
NetworkWired Ethernet recommended; tested on 10 GbE
TargetsStandard iSCSI. Tested: TrueNAS, Linux LIO / targetcli
AuthenticationNone, CHAP, mutual CHAP
IntegrityCRC32C header and data digests (optional)
File systemsAPFS, Mac OS Extended (Journaled): read and write. exFAT, FAT, NTFS: read-only
Not in version 1Intel Macs, multipath (MPIO), one disk on two Macs at once
For storage vendors

Qualify BeamDisk with your iSCSI targets.

Make storage servers, SANs or iSCSI target software? Get in touch to discuss qualifying BeamDisk with your targets.

Get in touch

  • Free of charge

    We work with your team to do the qualification, at no cost to you.

  • Fixed on our side

    What the testing turns up in BeamDisk, we fix.

  • Listed as tested

    When your target passes, we list it as tested on our compatibility page, with the configuration we tested.

Pricing

Free for home. Licensed for work.

Download BeamDisk free and use every feature for 30 days. After that, home use stays free with one server and up to 2 disks, and a one-time $25 purchase unlocks everything, for good.

  • Free trial

    Everyone, at home or at work

    $0every feature for 30 days

    • Every feature, unlocked
    • No account, no card
  • Home

    Personal, non-commercial use

    $0forever, after the trial

    • One storage server
    • Up to 2 disks
    • You connect your disks yourself (Connect at login is Pro)
  • Pro

    Anyone, at home or at work

    $25once, in the app

    • Every feature, permanently
    • Any number of servers and disks
    • Connect at login
    • The command-line tool
    • Personal use: your Macs on your Apple Account. Business use: one Mac per purchase
  • Business

    Organizations

    $25per Mac, through Apple Business Manager

    • The separate BeamDisk for Business app
    • Exactly what Pro unlocks
    • Bought in volume, assigned to Macs by your MDM

Using BeamDisk for work, at a business or for paid work at home, needs Pro or BeamDisk for Business after the trial, one purchase per Mac. Pricing and licensing

FAQ

Questions, answered.

Is there an iSCSI initiator for Macs with Apple Silicon?

Yes. BeamDisk connects a Mac with Apple Silicon to iSCSI targets on a storage server or SAN, and runs on macOS 27 or later.

Does BeamDisk need a kernel extension or Reduced Security?

No. It installs from the Mac App Store like any app and asks you to turn it on once in System Settings. There's no Recovery-mode restart, and your Mac's security settings don't change.

Which iSCSI targets does it work with?

BeamDisk uses standard iSCSI. It's tested with TrueNAS and with Linux targets (LIO / targetcli). The compatibility page keeps the current list.

Can I use an iSCSI disk for Time Machine?

Yes. Set it up once in BeamDisk's settings (it needs an administrator's approval), then choose the disk in Time Machine. How to set it up.

How fast is BeamDisk?

On 10 GbE to a Linux iSCSI target with SATA SSDs, BeamDisk read at 1,230 MB/s and wrote at 1,236 MB/s, each measured on its own, over 99% of what the link can carry, and did 20.2K random 16 KiB reads and 24.0K random 16 KiB writes per second. Reading and writing at the same time, it moved 1,844 MB/s in all, and 26.2K random 16 KiB operations a second at 70% reads. Your numbers depend on your server and network; BeamDisk's Test Speed measures them. The benchmarks.

Can two Macs use the same iSCSI disk?

Not at the same time. BeamDisk takes exclusive access, so a second computer is refused rather than corrupting the disk. Remove the disk on one Mac to use it on another.

What happens if the network drops or the server restarts?

BeamDisk holds writes for up to 60 seconds (adjustable from 15 to 300) and reconnects automatically. Apps only see errors if the outage lasts longer than that.

Is BeamDisk free?

It's free to download, with every feature for 30 days. After that it stays free for home use, with one server and up to 2 disks, and a one-time $25 in-app purchase unlocks every feature permanently. Pricing.

Can I use the free version at work?

No. Business and commercial use need a license after the trial, one per Mac: Pro ($25 in the app), or BeamDisk for Business for organizations.

Does BeamDisk support CHAP?

Yes, CHAP and mutual CHAP. Secrets are kept in your Keychain.

Which file systems can I use on the disk?

APFS and Mac OS Extended (Journaled) are read and write. exFAT, FAT and NTFS disks attach read-only.

Does BeamDisk collect any data?

No. There's no account and no analytics; it connects only to your storage, and to Apple for purchases and updates.

Does it support multipath (MPIO) or Intel Macs?

Not in version 1.

Is the iSCSI traffic encrypted?

iSCSI itself isn't encrypted; CHAP authenticates both ends. Keep storage traffic on a trusted network or VLAN, as with any iSCSI initiator.

Download

Beam your LUNs to your Mac.

Free to download. Free for home use.