port forwarding with ssh to access horizon running in vagrant VM which run in remote baremetal node

$ssh -L 10.140.15.64:8081:192.168.56.20:80 vagrant@192.168.56.20
password: vagrant

* Run this command in baremetal node "10.140.15.64".
* 10.140.15.64 === IP of baremetal node where vagrant with virtualbox is running.
* 192.168.56.20 === Hostonly adapter IP of virtualbox VM running on baremetal node
* We can access horizon running in 192.168.56.20 from our laptop like http://10.140.15.64:8081/dashboard

1)
configuration of bare-metal node where vagrant VM is running

a)
physical interface of baremetal node
$ ifconfig eth3  <====
eth3      Link encap:Ethernet  HWaddr 11:11:11:11:11:11 
          inet addr:10.140.15.64  Bcast:10.140.15.255  Mask:255.255.255.0
          inet6 addr: fe80::3aea:a7ff:fe11:7ac9/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:86183263 errors:0 dropped:0 overruns:0 frame:0
          TX packets:38261525 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:26521496912 (26.5 GB)  TX bytes:6480246966 (6.4 GB)

b)
Hostonly adapter interface of virtualbox
$ ifconfig vboxnet0  <====
vboxnet0  Link encap:Ethernet  HWaddr 0a:00:27:00:00:00 
          inet addr:192.168.56.1  Bcast:192.168.56.255  Mask:255.255.255.0
          inet6 addr: fe80::800:27ff:fe00:0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:255940 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B)  TX bytes:79238841 (79.2 MB)
c)
routes in baremetal node
$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.140.15.1     0.0.0.0         UG    0      0        0 eth3
10.140.15.0     0.0.0.0         255.255.255.0   U     0      0        0 eth3
169.254.169.254 10.140.15.4     255.255.255.255 UGH   0      0        0 eth3
192.168.56.0    0.0.0.0         255.255.255.0   U     0      0        0 vboxnet0 <====

2)
configuration of vagrant VM

a)
$ ifconfig br-ex <====
br-ex     Link encap:Ethernet  HWaddr 08:00:27:ad:e2:80 
          inet addr:192.168.56.20  Bcast:192.168.56.255  Mask:255.255.255.0
          inet6 addr: fe80::f474:80ff:fef7:422f/64 Scope:Link
          inet6 addr: 2001:db8::2/64 Scope:Global
          UP BROADCAST RUNNING  MTU:1500  Metric:1
          RX packets:676 errors:0 dropped:0 overruns:0 frame:0
          TX packets:479 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:119840 (119.8 KB)  TX bytes:675959 (675.9 KB)

b)
run tcpdump in br-ex interface to check the traffic
$ sudo tcpdump -i br-ex