VPP/Using mTCP user mode TCP stack with VPP
NOTE: This page is under construction.
This example shows how to configure and run sample client/server applications using user mode mTCP in 2 linux namespaces (or containers) which communicate through VPP via netmap virtual interfaces.
In this setup we use 2 different namespaces called vpp1 and vpp2 and two sample applications epserver and epwget available with mTCP.
Setup
NETMAP
Download the sources from the upstream repository using following command:
git clone git@github.com:vpp-dev/netmap.git OR https://github.com/vpp-dev/netmap/archive/master.zip
Enter LINUX directory and configure netmap. To compile only NETMAP/VALE (using unmodified drivers):
./configure --no-drivers make make apps sudo insmod netmap.ko
To verify that module is loaded, you can use the following command which should show you (Module-name , Size and Used by):
lsmod | grep netmap
VPP
We assume that you are already running vpp. If it is not the case, please follow the following link to build, install and test VPP:
https://wiki.fd.io/view/VPP/Build,_install,_and_test_images
mTCP
Download the sources using following command:
git clone git@github.com:vpp-dev/mtcp.git OR https://github.com/vpp-dev/mtcp/archive/master.zip
Enter mtcp root directory and configure mtcp. To compile for netmap module:
./configure --enable-netmap make
Namespaces Create namespaces, using the following commands:
sudo ip netns add vpp1 sudo ip netns add vpp2 sudo ip netns show vpp1 vpp2
Configure Interfaces
VPP
Run VPP/VPP-lite and create netmap interfaces using the VPP debug Command-line Interface (CLI):
        create netmap name vale00:vpp1 hw-addr 02:FE:3F:34:15:9B pipe master
        create netmap name vale00:vpp2 hw-addr 02:FE:75:C5:43:66 pipe master
        set int state netmap-vale00:vpp2 up
        set int state netmap-vale00:vpp1 up
        set int l2 xcon netmap-vale00:vpp1 netmap-vale00:vpp2
        set int l2 xcon netmap-vale00:vpp2 netmap-vale00:vpp1
 
To verify that interfaces have been created and up, use the following command:
vpp# show int
              Name               Idx       State          Counter          Count     
local0                            0        down      
netmap-vale00:vpp1                5         up       
netmap-vale00:vpp2                6         up       
pg/stream-0                       1        down      
pg/stream-1                       2        down      
pg/stream-2                       3        down      
pg/stream-3                       4        down      
Modify Config Files
mTCP
In <mTCP-ROOT>/apps/example/, you can change the epserver.conf file and epwget.conf.
example epserver.conf file:
# module io = netmap # Port port vale00:vpp1}0 # Hw addr of port hw_addr = 02:fe:3f:34:15:9b # Ip addr of port ip_addr = 10.0.42.3 # Netmask of port netmask = 255.255.255.0 # Maximum concurrency per core max_concurrency = 10000 # Maximum number of socket buffers per core max_num_buffers = 10000 # Receive buffer size of sockets rcvbuf = 16384 # Send buffer size of sockets sndbuf = 16384 # TCP timeout seconds tcp_timeout = 30 # TCP timewait seconds tcp_timewait = 0 # Interface to print stats stat_print = vale00:vpp1}0
example epwget.conf file
# module io = netmap # Port port vale00:vpp2}0 # Hw addr of port hw_addr = 02:fe:75:c5:43:66 # Ip addr of port ip_addr = 10.0.42.2 # Netmask of port netmask = 255.255.255.0 # Maximum concurrency per core max_concurrency = 10000 # Maximum number of socket buffers per core max_num_buffers = 10000 # Receive buffer size of sockets rcvbuf = 16384 # Send buffer size of sockets sndbuf = 8192 # TCP timeout seconds tcp_timeout = 30 # TCP timewait seconds tcp_timewait = 0 # Interface to print stats stat_print = vale00:vpp2}0
Test
Enter to <mtcp root>/apps/example/, and create a new directory using the following command:
mkdir www cd www/ nano index.html
Write something in the file, save and close it.
Enter to <mtcp root>/apps/example/ and use the following command to start the http server:
sudo ip netns exec vpp1 ./epserver -p www/ -f epserver.conf -c 1 -N 1
On another terminal, Enter to <mtcp root>/apps/example/ and use the following command to start the epwget client:
sudo ip netns exec vpp2 ./epwget 10.0.42.3/index.html 1 -N 1 -s 2 -o output.txt
To VPP CLI and Use the command show interface:
vpp# show int
              Name               Idx       State          Counter          Count     
local0                            0        down      
netmap-vale00:vpp1                5         up       rx packets                   501
                                                     rx bytes                   48460
                                                     tx packets                   601
                                                     tx bytes                   51860
netmap-vale00:vpp2                6         up       rx packets                   601
                                                     rx bytes                   51860
                                                     tx packets                   501
                                                     tx bytes                   48460
pg/stream-0                       1        down      
pg/stream-1                       2        down      
pg/stream-2                       3        down      
pg/stream-3                       4        down      
You can also use the command  cat  to see the http response output:
cat output.txt.0 HTTP/1.1 200 OK