USBMON

A tool to enumerate, list and monitor USB devices connected to a Linux host.

• Print a list of connected devices with USB path, properties and speed
• Monitor udev events such as connect or disconnect and print them with a timestamp
• Collectd plugin mode
• JSON stream mode

Requirements

requires libudev-dev

Usage

Flags

usbmon [-n] [-c] [-j]
  -n do not monitor events
  -c collectd exec plugin mode
  -j json stream mode

Collectd plugin mode

Usbmon can operate as collectd exec plugin.

Add a new type to /usr/share/collectd/types.db:

usb_devices             connected:GAUGE:0:U, adds:COUNTER:U:U, removes:COUNTER:U:U

Create exec plugin config file, /etc/collectd/collectd.conf.d/usbmon.conf:

LoadPlugin Exec
<Plugin exec>
  Exec "nobody" "/var/lib/collectd/plugins/usbmon" "-c"
</Plugin>

Install usbmon in the plugins directory and restart collectd.

JSON Stream mode

Usbmon can generate a streaming JSON output with per port events. Streaming JSON is basically a never ending array. To use in Go:

type evt struct {
  Port   string
  Serial string
  Event  string
  Speed  float32
}
u := exec.Command("usbmon")
o, _ := u.StdoutPipe()
u.Start()
d := json.NewDecoder(o)
d.Token() // read opening [
for d.More() {
  var e evt
  d.Decode(&e)
  fmt.Printf("%+v\n", e)
}

License

• Usbmon code is licensed under Apache 2.0
• Usbmon links with libudev which is GPL2.1

Disclaimer

This is not an official Google product.