example2

Example 2: Label Edge Router using P4 Hardware

Example 2 is designed to show the capability of TableVisor to translate between different configuration protocols. In this example use-case a transparent translation between OpenFlow 1.3 and the proprietary configuration protocol used by the Netronome Agilio CX P4 NICs is performed. The following picture presents the example setup in which we realize an OpenFlow capable MPLS label edge router using a single P4 hardware card.

The MPLS label edge router is realized using 4 tables. The acl_tbl performs common access control. The mpls_tbl performs an MPLS_POP operation removing the MPLS header from the packet. Following, the routing_tbl sets the ETH_DST field based on the destination IP address. Finally, the switch_tbl performs an OUTPUT action to forward the packet to the next hop based on the destination mac address.

P4 Program (including annotations)

The used P4 programm is located in example2/mplsProgram.p4. Here, the annotations are particularly important for TableVisor. For example, note the table and field annotations, as seen in the acl_tbl:

// @TV table 0
table acl_tbl {
    reads {
        // @TV field eth_type
        eth.etype : exact;
        // @TV field eth_dst
        eth.dst : exact;
    }
    // [...] (actions)
}

Hereby, the table ID 0 is mapped to the name acl_tbl when used with the RTECLI tool, and the OpenFlow field ETH_TYPE is translated to the P4 field eth.etype.

In addition, multiple OpenFlow actions must be mapped to a single P4 action, as P4 only supports one action per match. In the following section:

// @TV action MPLS_POP   POP_ETHERTYPE=etype
// @TV action GOTO_TABLE_2
action mpls_pop(etype) {
    remove_header(mpls);
    modify_field(eth.etype, etype);
}

... the mpls_pop P4-action is linked to the MPLS_POP and GOTO_TABLE instructions in OpenFlow. Note that P4 implicitly executes the GOTO_TABLE instruction towards the next table in its control flow.

Setup and Startup

Adjustments (IP and CLI path)

You may skip this section if everything (TableVisor, ONOS and the P4 card) is running on the same machine.

In the file example2/TVconfig.yml:

# Connection from TV to the Controller
upperLayerEndpoints:
  - name: MyConnectionToOnos
    type: OPENFLOW            # upperlayer.UpperLayerType
    ip: 127.0.0.1
    port: 6653
    reconnectInterval: 5000   # default: 10000 ms

... adjust the ip such that TableVisor is able to connect to the ONOS instance.

In the switch section:

# Connection from TV to the Switches
lowerLayerEndpoints:
  - name: P4Switches
    type: P4_NETRONOME
    rtecliPath: /opt/nfp-sdk-6.0.1/p4/bin/rtecli
    switches:
      - dataplaneId: 100
        rteIp: 172.16.35.11   # You probably need to change this!
        rtePort: 20206
        numberOfPorts: 2
        [...]

... check the rtecliPath and the rteIp to point towards the CLI binary and your Netronome P4 host.

ONOS

Assuming ONOS was unpacked into the folder ./onos-1.11.1, execute the following command:

./onos-1.11.1/bin/onos-service start

ONOS should initialize and present its own terminal. If no errors occur, you can access its web interface via http://127.0.0.1:8181/onos/ui/login.html to test whether it's running properly. Log in with the user onos and password rocks and open the Applications settings (click on the three bars in the top left). Here, only enable the OpenFlow Base Provider (org.onosproject.openflow-base) application. Therefor, select it and click on the Play-Button in the top right of the screen.

(Make sure that the applications from example1 are disabled at this point! In order to reset the flow rules afterwards, type wipe-out please in the ONOS terminal.)

TableVisor

When located in the main repository folder, after compiling TableVisor via mvn package, run the following command:

java -jar target/tablevisor-standalone-3.0.0-SNAPSHOT-jar-with-dependencies.jar example2/TVconfig.yml

The output should look as follows:

2017-10-09 14:48:29,951 [main] INFO  - Using configuration file /home/alex/w/17/tablevisor-github/example2/TVconfig.yml
2017-10-09 14:48:30,043 [main] INFO  - Starting TableVisor
2017-10-09 14:48:30,044 [main] INFO  - Initializing ControllerLogApplication...
2017-10-09 14:48:30,044 [main] INFO  - Initializing OneTransparentSwitchApplication...
2017-10-09 14:48:30,044 [main] INFO  - Initializing P4ControlApplication...
2017-10-09 14:48:30,141 [main] INFO  - Initializing SwitchLogApplication...
2017-10-09 14:48:30,144 [main] INFO  - Waiting for all (1) switches to connect...
2017-10-09 14:48:30,147 [main] INFO  - Switch ID '100' of type 'P4_NETRONOME' registered
2017-10-09 14:48:30,147 [main] INFO  - All switches connected.
2017-10-09 14:48:30,153 [Thread-1] INFO  - MyConnectionToOnos - Attempting connection to control plane 127.0.0.1:6653
[...]

Flow Rules

The following flow rules are going to be installed in this simple scenario:

Table	Match	Actions
acl_tbl (0)	ETH_TYPE=MPLS and ETH_DST=00:00:00:00:00:01	GOTO_TABLE 1
mpls_tbl (1)	(empty)	MPLS_POP and GOTO_TABLE 2
routing_tbl (2)	ETH_TYPE=IPv4 and IPv4_DST=10.100.100.10	ETH_DST=00:00:00:00:00:02 and GOTO_TABLE 3
switch_tbl (3)	ETH_DST=00:00:00:00:00:02	OUTPUT PORT=1

Again, while located in the main folder, execute the following command to install the flow rules:

curl -u onos:rocks -H 'Content-type: application/json' -X POST -d '@example2/onosRules.json' 'http://127.0.0.1:8181/onos/v1/flows'

Note that you may have to adjust the IP address towards ONOS again.

You can now observe that ONOS installs the rules on the device (in the Devices section, select of:0102030405060708 and click on the flow view icon in the top right). However, note that P4 does not implement default packet and byte counters, hence their information is omitted here.

You may check the rules on the P4 card, e.g., via the RTECLI interface:

rtecli --rte-port 20206 --rte-host 172.16.35.11 tables --table-name routing_tbl list-rules

The result should look as follows:

[TableEntry(priority=15, rule_name='r008500002447597e', default_rule=False, actions='{  "type" : "set_dst_mac",  "data" : { "mac" : { "value" : "00:00:00:00:00:02" } } }', match='{ "eth.etype" : {  "value" : "0x800" }, "ipv4.dstAddr" : {  "value" : "10.100.100.10" } }')]