Creating an Interface¶
Skills to be Learned¶
- Create a veth interface in Linux host 
- Assign an IP address to one end of the veth interface in the Linux host 
- Create a vpp host-interface that connected to one end of a veth interface via AF_PACKET 
- Add an ip address to a vpp interface 
VPP commands learned in this exercise¶
Initial State¶
The initial state here is presumed to be the final state from the previous sections of the tutorial.
Create veth interfaces on host¶
In Linux, there is a type of interface call ‘veth’. Think of a ‘veth’ interface as being an interface that has two ends to it (rather than one).
Create a veth interface with one end named vpp1out and the other named vpp1host
$ sudo ip link add name vpp1out type veth peer name vpp1host
Turn up both ends:
$ sudo ip link set dev vpp1out up
$ sudo ip link set dev vpp1host up
Assign an IP address¶
$ sudo ip addr add 10.10.1.1/24 dev vpp1host
Display the result:
$ ip addr show vpp1host
5: vpp1host@vpp1out: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
  link/ether e2:0f:1e:59:ec:f7 brd ff:ff:ff:ff:ff:ff
  inet 10.10.1.1/24 scope global vpp1host
     valid_lft forever preferred_lft forever
  inet6 fe80::e00f:1eff:fe59:ecf7/64 scope link
     valid_lft forever preferred_lft forever
Create vpp host-interface¶
Make sure VPP is running, if not start it.
$ ps -eaf | grep vpp
vagrant   2141   903  0 05:28 pts/0    00:00:00 grep --color=auto vpp
# vpp is not running, so start it
$ sudo /usr/bin/vpp -c startup1.conf
These commands are run from the vpp shell. Enter the VPP shell with the following command:
$ sudo vppctl -s /run/vpp/cli-vpp1.sock
    _______    _        _   _____  ___
 __/ __/ _ \  (_)__    | | / / _ \/ _ \
 _/ _// // / / / _ \   | |/ / ___/ ___/
 /_/ /____(_)_/\___/   |___/_/  /_/
vpp#
Create a host interface attached to vpp1out.
vpp# create host-interface name vpp1out
host-vpp1out
Confirm the interface:
vpp# show hardware
              Name                Idx   Link  Hardware
host-vpp1out                       1     up   host-vpp1out
Ethernet address 02:fe:d9:75:d5:b4
Linux PACKET socket interface
local0                             0    down  local0
local
Turn up the interface:
vpp# set int state host-vpp1out up
Confirm the interface is up:
vpp# show int
              Name               Idx    State  MTU (L3/IP4/IP6/MPLS)     Counter          Count
host-vpp1out                      1      up          9000/0/0/0
local0                            0     down          0/0/0/0
Assign ip address 10.10.1.2/24
vpp# set int ip address host-vpp1out 10.10.1.2/24
Confirm the ip address is assigned:
vpp# show int addr
host-vpp1out (up):
  L3 10.10.1.2/24
local0 (dn):
