Test connectivity of multiple devices

Background

Running multiple Cuttlefish virtual devices can be done by executing the following command:

launch_cvd --num_instances=n

When you are running two or more instances using --num_instances flag, instances share the connectivity medium for Wi-Fi and Bluetooth. This setting allows the Cuttlefish instances to discover and connect to each other via Bluetooth and Wi-Fi without additional action.

However, if you are executing multiple instances by using the --base_instance_num flag and multiple launch_cvd invocations, you need to specify wmediumd's vhost server path to share Wi-Fi medium, and also prevent launching multiple VM instances for AP.

Multi-device launch example

The following commands show how to launch two Cuttlefish instances that share the Wi-Fi medium using serial execution of launch_cvd.

launch_cvd

launch_cvd --base_instance_num=2 \
  --vhost_user_mac80211_hwsim=$HOME/cuttlefish_runtime.1/internal/vhost_user_mac80211 \
  --ap_kernel_image="" --ap_rootfs_image="" #Prevent launching multiple VM instances for AP

Bluetooth

The Cuttlefish bluetooth implementation is supported by rootcanal and can be controlled with the Web UI command line console.

In the console, there are several commands that allow for the control of bluetooth on the guest device:

Command	Description
`list`	List current devices and phys
`add` `DEVICE_TYPE` `[ARGS]`	Create new device of type `DEVICE_TYPE`
`del` `DEVICE_INDEX`	Delete a device
`add_phy` `PHY_TYPE`	Add new phy with `PHY_TYPE`
`del_phy` `PHY_INDEX`	Delete a phy
`add_device_to_phy` `DEVICE_INDEX` `PHY_INDEX`	Add a device to phy
`del_device_from_phy` `DEVICE_INDEX` `PHY_INDEX`	Delete a `device from phy
`add_remote` `HOSTNAME` `PORT PHY_TYPE`	Add a remote Rootcanal as device and register it to phy

Device type and args
`beacon` `[MAC_ADDRESS]` `[ADVERTISE_INTERVAL]`
`scripted_beacon` `[MAC_ADDRESS]` `[CONFIG_PATH]` `[EVENTS_PATH]`
`keyboard` `[MAC_ADDRESS]` `[ADVERTISE_INTERVAL]`
`loopback` `[MAC_ADDRESS]` `[ADVERTISE_INTERVAL]`
`sniffer`

Wi-Fi

wmediumd_control

wmediumd_control is a command-line tool that controls Wi-Fi connectivity medium. The tool has the following commands to manipulate Wi-Fi:

Command	Description
`set_snr` `MAC_ADDR1` `MAC_ADDR2` `SNR_VALUE`	Set SNR value (0~255) between two stations
`start_pcap` `PCAP_FILE_PATH`	Start capturing all frames transmitted to air and stores it to .pcap file
`stop_pcap`	Stop and finalize current packet capture
`list_stations`	List all stations attached to wmediumd
`reload_config` `[CONFIG_FILE_PATH]`	Reload wmediumd configuration with `CONFIG_FILE_PATH`, if `CONFIG_FILE_PATH` is omitted, reload currently loaded config file
`set_position` `MAC_ADDR` `X_POSITION` `Y_POSITION`	Set position of the station in two-dimensional space

OpenWRT

If you want to connect to OpenWRT (Access Point), you can use either ssh or the admin webpage.

Connection Type	Method
ssh	ssh root@192.168.96.2
Admin webpage	https://192.168.96.2