ATENtion

A fast, native Windows console (KVM-over-IP) client for Supermicro servers with ATEN/Pilot BMCs. It is a from-scratch replacement for the old Java iKVM viewer.

Why this exists

If you run an older Supermicro board, the only console option the BMC hands you is the ATEN Java iKVM viewer, launched through Java Web Start. That path has aged badly:

• Java Web Start and javaws were removed from modern JDKs, so the launcher often does not run at all without an old JRE or OpenWebStart.
• Every session is a fresh .jnlp file full of single-use tokens that expire, so you re-download it from the web UI each time.
• You click through Java security prompts on every launch (assuming you've modified java.security correctly to even permit clicking through).
• The viewer is clunky, and the bundled TLS certificates have since expired, which breaks the connection outright on a correct clock.

ATENtion skips all of that. It speaks the ATEN protocol directly as a native application, so there is no Java, no Web Start, and no .jnlp juggling. Enter the BMC address and credentials and you are on the console.

Status and tested hardware

This has been tested on one board thus far: my Supermicro X9DRH-7F (X9 generation, with an ATEN/Pilot BMC). Other ATEN/Pilot-based Supermicro BMCs across the X9, X10, and X11 generations should work, but they are presently untested.

Features

• Live video, keyboard, and mouse over the console.
• Mouse in Absolute mode (the pointer mode BIOS, UEFI, and most operating systems expect).
• Power control: On, Off, Reset, and Soft Off (ACPI), plus Ctrl+Alt+Del.
• Virtual media: mount a local .iso as a read-only CD-ROM, by menu or by dragging the file onto the video.
• Screenshots of the current frame, saved as PNG.
• Paste the clipboard into the host as keystrokes.
• Send-key macros: Alt+Tab, Alt+F4, Alt+Space, Ctrl+Esc, the Windows key, Print Screen, and any arbitrary custom combination.
• View options: fullscreen, fit-to-window, actual size (1:1), and smooth or crisp scaling.
• Auto-reconnect after a dropped link.
• A live Session Info panel (endpoint, transport, resolution, control state, frame rate, throughput, uptime).
• Optional diagnostic logging, off by default.

Requirements

• Windows 10 or later (may work on earlier - untested).
• .NET Framework 4.8.

Build

With the .NET SDK:

dotnet build ATENtion.slnx -c Release

The application is produced at src/ATENtion.App/bin/Release/net48/ATENtion.exe. Visual Studio 2022 also opens and builds ATENtion.slnx directly.

Connecting

There are two ways to connect. The Connect dialog gates its fields based on the "Arm via web" checkbox.

• Auto-arm (recommended). Leave "Arm via web" ticked and enter the BMC web user name and password. The app logs into the BMC, acquires a fresh single-use session token, and picks the port and TLS setting for you.
• Manual token. Untick "Arm via web", then paste a session token and set the port and TLS yourself. This is for when you already hold a token or do not want the app to log in to your BMC.

If the first connection fails with a TLS or certificate error, that is expected on many boards. See the FAQ entry on the expired certificate below.

How it works

ATENtion is a native client for the ATEN variant of the RFB/VNC protocol that Supermicro iKVM uses. It connects with mutual TLS to the BMC KVM port (5900 by default), or in plain text to the iKVM port (63630) when KVM SSL is turned off on the BMC. Video, input, power, and virtual media all utilise the same connection.

Project layout

• src/ATENtion.Core - the protocol, video codec, input, crypto, and virtual-media logic.
• src/ATENtion.App - the WPF application and its windows.
• tests/ATENtion.Tests - the unit tests.

License

MIT. See LICENSE.

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FAQ

The connection fails with a TLS handshake or certificate error. What now?

The client certificate Supermicro bundles with iKVM has expired (around mid-2026), so a TLS handshake on a correctly-set clock is refused. Two ways around it:

1. Roll the BMC clock back. In the BMC web UI, under Configuration > Date and Time, set the date to before the expiry (for example 2024), then reconnect. If TLS still fails, temporarily set your Windows clock back to the same period as well. Windows (SChannel) will not present an expired client certificate while its own clock says the certificate is out of date, so both clocks may need to agree.
2. Disable KVM SSL on the BMC. Turn off SSL/encryption for the KVM console in the BMC web UI. The BMC then serves the plain-text iKVM port (63630) and no certificate is involved. ATENtion connects to it directly.

You can also drop a renewed client.pfx next to ATENtion.exe. A certificate file found beside the executable overrides the one built into the application.

Auto-arm or token mode, and why?

Auto-arm is the easy path. You give the app your BMC web user name and password, it logs in, fetches a fresh single-use token, and reads the correct port and TLS setting from the BMC. Token mode is for when you already have a session token (for example from a .jnlp you downloaded) or you do not want the app to log in for you; you then set the port and TLS by hand. Because tokens are single-use and expire quickly, auto-arm is less trouble.

Which port, and TLS or plain text?

By default the console is mutual TLS on port 5900. If KVM SSL is disabled on the BMC, it is plain text on port 63630 instead. In auto-arm mode the app chooses automatically based on the BMC's stunnel setting. In token mode you choose.

The mouse does not track properly.

Only Absolute pointer mode is implemented. That is the mode BIOS, UEFI, and most operating systems use, so it covers the common cases. Relative and Single modes are not done yet.

How do I mount an ISO?

Use Storage > Mount ISO, or drag an .iso file onto the video. It appears to the host as a read-only CD-ROM. Unmount it from the Storage menu. This has been a bit buggy for me, so please raise an issue if you encounter any issues.

Where are my settings and BMC password stored?

In user.config under %LOCALAPPDATA%. The BMC password is protected with DPAPI scoped to your Windows user, never stored in the clear.

What is in the log file, and is it safe to share?

Logging is off by default. When it is on, the log can contain your BMC IP address, hostname, and session token. Do not share it. The repository ignores *.log so a session log is never committed.

Will it work on my board?

It has only been verified on the X9DRH-7F. Other ATEN/Pilot-based Supermicro BMCs should work, but they are untested.

I am connected but the screen is black.

Use View > Refresh Screen. The real resolution is negotiated from the first video frame, so a refresh forces the BMC to send another full frame.