Introduction

etherws is an implementation of Ethernet over WebSocket tunnel based on Linux Universal TUN/TAP device driver.

Usage

For example, if you want to make virtual ethernet link for VM1 and VM2 whose hypervisor's broadcast domains were split by router R:

+------------------+            +------------------+
| Hypervisor1      |            |      Hypervisor2 |
|  +-----+         |            |         +-----+  |
|  | VM1 |         |            |         | VM2 |  |
|  +--+--+         |            |         +--+--+  |
|     | (vnet0)    |            |    (vnet0) |     |
|  +--+--+         |            |         +--+--+  |
|  | br0 |         |            |         | br0 |  |
|  +--+--+         |            |         +--+--+  |
|     |            |            |            |     |
| (ethws0)  (eth0) |            | (eth0)  (ethws0) |
+----||--------+---+            +----+-------||----+
     ||        |        +---+        |       ||
     ||   -----+--------| R |--------+-----  ||
     ||                 +---+                ||
     ||                                      ||
     ``======================================''
          (Ethernet over WebSocket tunnel)

then you can type following commands.

on Hypervisor1:

# etherws server
# brctl addbr br0
# brctl addif br0 vnet0
# brctl addif br0 ethws0
# ifconfig br0 up

on Hypervisor2:

# etherws client --uri ws://<Hypervisor1's IP address>/
# brctl addbr br0
# brctl addif br0 vnet0
# brctl addif br0 ethws0
# ifconfig br0 up

If connection through this tunnel is unstable, then you may fix it by changing VM's MTU to under 1500.

Also etherws supports SSL/TLS connection (but authentication is not supported yet), so if you want to encrypt this tunnel, then you can use following options.

on Hypervisor1 (options keyfile and certfile were specified):

# etherws server --keyfile ssl.key --certfile ssl.crt

on Hypervisor2 (option uri's scheme was changed to wss):

# etherws client --uri wss://<Hypervisor1's IP address>/

History

0.2 (2012-05-16 JST)

• SSL/TLS connection support

0.1 (2012-05-15 JST)

• First release