29
+ − 1 These scripts can be used to graph the BGP peering connections in a network using the BGP protocol.
+ − 2
+ − 3 Some of the scripts will communicate with the BGP software, another script can be used to export the obtained information to a .dot file, which can then be converted to a graph file using graphviz. The scripts can run on different machines, and it is recommended to use routing information from multiple routes, to obtain an accurate view of the network.
+ − 4
+ − 5 Depending on the BGP software, one of the following scripts must be used to acquire the data:
+ − 6 - bgp_path_list_birg.sh (or .php) for the bird routing daemon
+ − 7 - bgp_path_list_quagga.sh (or .php) for the quagga/zebra routing daemon
+ − 8 - bgp_path_list_xml.php to convert existing dn42/diac42 .xml data
+ − 9
+ − 10 All these scripts will send their output to the stdout, so you either have to pipe them to another script, or redirect their output to a file (examples below).
+ − 11
+ − 12 Inside the scripts are a few configuration options. You should configure your local AS number (mynode/LOCALNODE variable) for proper operation. You may also change authentication parameters, for the quagga script.
+ − 13
+ − 14 To create the graph, you will need the path_list_to_dot.php script, this script expects the collected path data on STDIN, and will send the DOT-data to STDOUT (examples below). The DOT-data can be sent to one of the graphviz utilities (the dot command often performs best).
+ − 15
+ − 16 EXAMPLES
+ − 17
+ − 18 Graphing one single local bird instance
+ − 19 $ ./bgp_path_list_bird.sh | ./path_list_to_dot.php | dot -T png -o graph.png
+ − 20
+ − 21 Graphing one single quagga instance
+ − 22 $ ./bgp_path_list_quagga.sh | ./path_list_to_dot.php | dot -T png -o graph.png
+ − 23
+ − 24 Graphing data from one local bird instance and one quagga instance
+ − 25 $ ./bgp_path_list_bird.sh > /tmp/paths.txt
+ − 26 $ ./bgp_path_list_quagga.sh >> /tmp/paths.txt
+ − 27 $ ./path_list_to_dot.php < /tmp/paths.txt | dot -T png -o graph.png
+ − 28
+ − 29 You can combine data from as many routers as you like. More is better, because it will make the graph more accurate.
+ − 30
+ − 31 Or, in one single line:
+ − 32 $ (./bgp_path_list_bird.sh; ./bgp_path_list_quagga.sh) | ./path_list_to_dot.php < /tmp/paths.txt | dot -T png -o graph.png
+ − 33
+ − 34 Graphing a remote quagga instance using http:
+ − 35 $ wget http://remotehost/bgp_path_list_quagga.php -O - | ./path_list_to_dot.php < /tmp/paths.txt | dot -T png -o graph.png
+ − 36
+ − 37 Alternatively, you can use a cron job on the server to periodically update a static data file.
+ − 38
+ − 39 Graphing a remote instance using netcat:
+ − 40 server$ ./bgp_path_list_bird.sh | nc -l -p 9876
+ − 41 client$ nc remotehost 9876 | ./path_list_to_dot.php < /tmp/paths.txt | dot -T png -o graph.png
+ − 42
+ − 43 You can also use inetd/xinetd on the server side for a more permanent solution.
+ − 44
+ − 45
+ − 46 Be creative!