--- name: "bgpsim" section: "1" platform: "linux" package: "mrt" version: "2.2.2a-3" release: "Debian 3.1 (Sarge)" platforms: ["linux"] url: "https://new.carta.tech/bgpsim" --- # bgpsim(1) BGP4 routing environment simulator ## NAME bgpsim - BGP4 routing environment simulator ## DESCRIPTION Usage: bgpsim \[-i router\_id\] \[-p port\] \[-f file\] \[-v\] \[-o output\] BGPsim simulates complex BGP4 routing environments with possibly high levels of routing instability/change. BGPsim includes a perl program, BGPsim.pl, which is used to generate ASCII descriptions of BGP traffic for use with route\_btoa and sbgp. (The BGPsim Perl code is still quite rough.) Synopsis BGPsim \[-f configuration\_file\] \[-l routing table\] \[-v\] \[-s\] \[-m\] Options \-f configuration\_file\ Read the specified configuration file. By default, bgpsim tries\ to read ./bgpsim.conf. \-v\ Turn on verbose logging to standard output. This is useful to\ turn on logging before the debug commands are read in the\ configuration file. \-s\ By default, BGPSim does not set mandatory BGP attributes,\ including origin, nexthop and ASPath. If this flag is used,\ BGPsim will add these attributes and prepend the local AS to\ the ASPath. \-m\ Use a new dump format. Description By default, BGPsim looks for "./bgpsim.conf". The format of the configuration file is described below. BGPsim also has an interactive (Cisco Systems router-like) interface: telnet to port 5674 on the machine running BGPsim. NOTE: BGPsim does not include mandatory attributes by default. You will need to explicitly include a nexthop, origin, and apsath attribute in your BGPsim configuration. Also note that BGPSim does not prepend its own AS by default. Sample Configuration File A sample BGPsim configuration file is shown below. network-list 1 range 10.0.0.0/8 11.0.0.0 stability 10 jitter 4 map 1 ! route-map 1 set nexthop 198.108.60.8 set aspath 185 123 23 23 12 set origin igp ! network-list 2 range 192.32.0.0/24 192.32.255.0 stability 9 jitter 3 change 12 jitter 4 route-map 2 3 ! route-map 2 set next-hop 198.108.60.244 set as-path 185 123 23 23 12 set origin igp set community 56:123 set dpa as 56 121 set local-preference 23 ! route-map 3 set as-path 185 100 10 102 set origin igp set community 100:345 set dpa as 3 23 set local-preference 83 ! router bgp 185\ neighbor 198.108.60.244 remote-as 65\ neighbor 198.108.60.112 remote-as 165 This file describes two simulation processes, as defined by\ network-list 1 and 2, which changes routes to two BGP peers (AS 65 and\ AS165). The first simulation process, network-list 1, changes routes\ (10.0.0.0/8 and 11.0.0.0/8) as defined in range every 10 seconds. This\ simulates an announcement of the routes first, and then a withdrawal\ after 10 seconds. Ten seconds after the withdraw, the next\ announcement is propagated. Thus the announcements and withdraws are\ repeated every 10 seconds. These routes have attributes defined in\ route-map 1: nexthop is 198.108.60.8 and aspath is a sequence of 123\ 23 23 12. The second network list describes simulation of the range of routes\ from 192.32.0.0/24 to 192.32.255.0/24 (i.e. 192.32.1.0/24,\ 192\.32.2.0/24, etc.) All of these routes have an initial aspath of\ (123 23 23 12), a next-hop of 198.108.60.244, and others as defined in\ route-map 2. These attributes change every 12 seconds among route-maps\ 2 and 3. The peers (AS 65 and AS165) receive routing updates originated by\ these two simulation processes. Configuration Commands For information about the uii, debug, and access-list configuration\ commands, see Chapter 2, "Getting Started." In addition to the MRTd\ configuration commands, the following are available in BGPsim to\ simulate routing changes: network-list\ Defines a network-list with . This definition behaves like a routing\ process which generates routing changes within a range defined by\ range subcommand by an interval defined by stability subcommand,\ changing route attributes as specified by change and route-map\ subcommands. Options include: range Defines a range to announce and withdraw, starting with up to\ (inclusive). The range is along classful boundaries. stability\ \[jitter \] Defines an interval in second to change routes. Routes are\ announced first and then withdrawn after the interval. Thus, with\ the interval, announce and withdraw repeat. Jitter adds/subtracts\ a random number of seconds between 0 and \ to the\ interval. change\ \[jitter \] Defines an interval in second to change attributes of routes being\ announced. route-map subcommand defines a sequence. Jitter\ adds/subtracts a random \ of seconds from the timer. map ... Defines a sequence of route-maps to be used. The next route-mapis\ adopted after the interval defined in change subcommand. At the\ end of list, the first route-map is adopted as a next. The first\ route-map behaves as a default, that is, this is always adopted\ before adopting other route-maps. file ... Loads routes from routing table dump file rather than using a range of\ addresses. BGPSim also adds several commands to bgp router commands: neighbor stability Define stability for TCP peering session with this peer. Interactive Interface Commands The BGPsim interactive interface supports the following commands in\ addition to MRTd interactive interface commands: show simulation stop simulation start simulation You can find more documentation in /usr/share/doc/mrt/html/