pikvm/docs/multiport.md

# Multiport KVM over IP

There are many ways to do this, but the best and most documented one right now is to use the [ezCoo KVM switch](ezcoo.md).

Also, PiKVM can be connected to a multi-port HDMI/USB switch and the switch's buttons can be connected via optocouplers to [the Pi's GPIO to switch channels](gpio.md).

If your KVM switches channels using keyboard shortcuts, there is a chance that it will not be able to work with OTG (v2+ platform, see below), since it does not fully implement the USB stack. In this case, you will have to [use an Arduino board](arduino_hid.md) to emulate the keyboard & mouse (PiKVM supports this configuration).

!!! warning
    If you choose AIMOS, be aware that it has a back powering issue that you need to use work arounds for. Limitations are are listed below. Also please be aware that Arduino's will not work with the AIMOS KVM's.


## List of tested KVMs
Here the status is:

* ✔ - Everything is working as expected. There may be some subtleties.
* ☹ - Not everything works. Additional work is needed for some functions to work, like MSD.
* ✘ - The keyboard or mouse does not work at all, the switch loses the image, etc.

| Model | Status | Notes |
|:------|:-------|:------|
| [ezCoo EZ-SW41HA-KVMU3L 4x1 switch](https://www.easycoolav.com/products/hdmi20-switch-4x1-with-usb30-kvm-3-port-usbsupport-4k60hz-444-and-hdr-audio-breakout-36) ~~[ezCoo SW41HA HDMI 4x1 switch](https://www.easycoolav.com/products/hdmi20-switch-4x1-with-usb20-kvm-4-port-usbsupport-4k60hz-444-and-hdr-audio-breakout)~~ (legacy) | ✔ | [Using with PiKVM](ezcoo.md) - 4 Port is the ONLY supported KVM, 2 Port does not work the same and is not supported |
| [eccoo EZ-SW41HA-KVMU3P 4x1 switch](https://www.amazon.com/gp/product/B09ZKZK7ZB) |  ✔ |  make sure you buy the with hotkey version as that has the control port | 
| [ezcoo EZ-SW41H21-KVMU3P 8K 4x1 switch](https://www.easycoolav.com/products/8k-hdmi-kvm-switch-4x1-with-usb30-kvm-4k120hz-hotkey-switch) |  ✔ | Does NOT have a control port. MSD Works. Can be managed through key combo (ctrl+ctrl+#)
| [TESmart 8 PORT - HDMI KVM SWITCH](https://buytesmart.com/collections/8-ports) |  ✔ | Use OTG with USB 2.0 Hub only, no hotkey support. Switching available with serial or IP-to-serial interface using fixed IP (/31 peer-to-peer addressing supported). Can be managed [via WebUI](tesmart.md) or [CLI tool](https://github.com/bbeaudoin/bash/tree/master/tesmart) |
| [XH-HK4401 4-port HDMI USB KVM Switch](https://www.aliexpress.com/item/4000849336545.html) | ✔ | [Using with PiKVM](xh_hk4401.md) - USB MSD works, requires the HDMI backpower solutions found below |
| [Ali's noname](https://a.aliexpress.com/_BSpS8t) | ☹ | Limitations are listed below  |
| [AIMOS 8-port HDMI USB-C KVM Switch](https://www.amazon.de/AIMOS-Umschalter-Tastatur-unterst%C3%BCtzen-verbunden/dp/B08FR5K111/) | ☹ | Similar to Ali's noname model, available in 4/8port editions, has same HDMI bridge boot problem/solution using a Marmitek 312 UHD HDMI splitter. ONLY supports HotKey switching.  Limitations are are listed below |
| [Aten CS1758 8-port PS/2 / USB VGA KVM switch](https://www.aten.com/global/en/products/kvm/rack-kvm-switches/cs1758/) | ☹ | Older Aten switches can be had for cheap and can be a viable alternative. Devices are connected via PS/2 so USB media support does not work. The setup relies on a VGA-> HDMI adapter to make the video signal work and there can be issues with unsupported VGA resolutions with some adapters. KVM hotkeys and switching all work and so does mouse and keyboard. |

Limitations:

* HDMI backpower solutions:
    * See [here](https://github.com/pikvm/pikvm/issues/128)
    * See [here](https://github.com/pikvm/pikvm/issues/382) - Advanced soldering required
    * [This loop capture device](https://www.amazon.com/gp/product/B08B346353)
    * v3 HAT v3.3 (Kickstarter model and later) also takes care of the back power issue
* MSD workaround (will not work OOB)
    * RPi4 OTG needs to be in the KB port for mouse and KB funtionality, ZeroW is required and needs to be connected to the HUB port for MSD functionality - ✔**KNOWN WORKING**✔
    * See [here](https://github.com/pikvm/pikvm/issues/371) - Advanced soldering required - allows use of GPIO menu to change input