Deskflow

What Deskflow does

Deskflow is a free, open source keyboard and mouse sharing tool, the kind of program usually called a software KVM. One computer is configured as the server and keeps the physical keyboard and mouse; the others run as clients. Moving the pointer off the edge of one screen makes it appear on the neighbouring machine, and typing follows the pointer, so a desk with two or three computers behaves like a single machine with several monitors. The clipboard can be shared as well, which means text copied on one computer can be pasted on another. Connections are encrypted, screens can be arranged to match their physical layout, and clients can be locked or sent to sleep from the server. The project is a community continuation of the ideas behind Synergy and Barrier, and is licensed under the GNU General Public License version 2.

How a typical setup works

The graphical configuration window is where the layout is described. On the server you add each client by hostname or address, arrange the screen icons so that the positional relationships match the real desk, and define the shared clipboard behaviour and any hotkeys for locking or switching. Each client runs the same program in client mode and points at the server. Once connected, a small status window lists the attached machines. The configuration is stored in a text file, so a working setup can be copied to a replacement machine, and a command line mode allows the same program to run unattended as a service or background process.

Settings, practical limits and care

The important knobs are the screen layout, the switch delay and corner behaviour on the server, the clipboard sharing options, and the TLS settings that protect the link. All machines must be able to reach each other over the network, which in practice means the same local network or a VPN; there is no relay service. The computers must also keep their own displays active, because this is not remote control and nothing is drawn on a screen that is switched off. Linux clients depend on the display server in use, and a Wayland session may need extra configuration compared with X11, while Windows and macOS generally work after the first-run permission prompts for input monitoring and accessibility. Firewall rules usually have to allow the chosen port.

When to choose something else

If you need to see and control a machine that has no monitor attached, this is the wrong tool and a remote desktop program is what you want. If the machines are on different networks or behind restrictive routers, a remote access service with a rendezvous server will connect where a direct link cannot. If you are sharing a single keyboard with a hardware switch, that remains simpler and works before any operating system has booted. And if the only goal is transferring files between machines, a file transfer or sync tool is more appropriate. Deskflow suits a permanent desk with several computers that are all powered on and all on the same network.