RAPATH(1)

📦

version 5.0.2+git20250321.41f65e2 · 2 versions

5.0.2+git20250321.41f65e2 · debian trixie, ubuntu questing, ubuntu resolute, ubuntu stonking (latest)
3.0.8.2 · debian bookworm, fedora 43, fedora 44, nixos 26.05, nixpkgs unstable, opensuse-leap 16.0, ubuntu jammy, ubuntu noble

, in debian trixie, ubuntu questing, ubuntu resolute, ubuntu stonking

✨ okay bestie, you asked about rapath(1) and I am SO ready ✨

it's a General Commands Manual page, it lives in section 1, and it's genuinely one of the coolest little argus tools out there. let's get into it 🫶

🌸 NAME 🌸

rapath — print traceroute path information from argus(8) data. that's it, that's the vibe. 💅

✨ SYNOPSIS ✨

rapath [-A] [-M [ aspath [dist] | asnode ] ] [-m fields ] [raoptions]
[-- filter-expression]

🦋 DESCRIPTION 🦋

okay so here's the tea. Rapath reads argus data from an argus-data source, and generates the path information that can be formulated from flows that experience ICMP responses. 🎀

the way this works is genuinely iconic: when a packet causes the creation of an ICMP response, for whatever reason, the intermediate node that generates the ICMP packet is, by definition, on the path. Argus data preserves this intermediate node address, and rapath uses that info to generate path information for arbitrary IP network traffic. no cap. 🔥

Rapath is principally designed to recover traceroute.1 traffic, so that if a trace is done in the network, argus will pick it up and record the intermediate nodes and the RTT for the volleys. but the method is generalized such that it also picks up routing loop conditions, when they exist in the observed packet stream. lowkey versatile. 💜

Rapath will generate argus flow records that have the src address, dst address and src ttl of the transmitted packet, aggregated so that the average duration, standard deviation, max and min rtt's are preserved. 🌈

and here's the important bit, bestie — the most accurate estimate of the actual Round-Trip Time (RTT) between a src IP address and an ICMP based intermediate node is the MinDur field. as the number of samples gets larger, the MinDur field approaches the theoretical best case minimum RTT. RTT's above this value will include variations in network and device delay. ⭐

when using the optional racluster.1 style flow descriptors, path information to and from CIDR based network addresses can be calculated, so that traces from and to multiple machines in the subnets can be grouped together. group project energy, but make it networking. 👑

and the cutest part?? the output of rapath can be piped into ranonymize.1, in order to share path performance information without divulging the actual addresses of intermediate routers. privacy slay. 🙈

💖 RAPATH SPECIFIC OPTIONS 💖

Rapath, like all ra based clients, supports a number of ra options including filtering of input argus records through a terminating filter expression. See ra(1) for a complete description of ra options. rapath(1) specific options are: ✨

-A — Draw a description of the path with a legend. 🗺️
-M pathmodes — set the path mode. the supported pathmodes are:
- node — print a series of nodes that represent the path (default). the main character, honestly.
- addr — print the IP addresses, instead of node labels.
- aspath [dist] — print the series of origin AS's along the path. optional dist adds the ttl range.
- asnode — print the series of nodes, preceded with their AS's along the path.
-m fields — Specify modifications to the default flow identifiers. the supported fields are:
- srcid — the observation domain source identifier.
- saddr[/len] — the source address, optionally as a CIDR address.
- daddr[/len] — the destination address, optionally as a CIDR address.

🦋 INVOCATION 🦋

Okay bestie, enough theory — let's actually run it. Here's a sample invocation of rapath(1). This call reads argus(8) data from inputfile and generates any path information, based on src and dst IP addresses, and writes the results to stdout. Slay.

         % rapath -r inputfile

                SrcId       SrcAddr  Dir      DstAddr            Inode sTtl       Mean     StdDev        Max        Min  Trans
         192.168.0.68  192.168.0.68   ->  128.2.42.10      192.168.0.1    1   0.000686   0.000037   0.000764   0.000627     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10       10.22.96.1    2   0.009329   0.002719   0.019935   0.007435     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10     208.59.246.2    3   0.010686   0.002619   0.020175   0.007698     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10    207.172.15.85    4   0.013988   0.007116   0.032652   0.008923     11
         192.168.0.68  192.168.0.68   ->  128.2.42.10    207.172.15.67    4   0.010188   0.000218   0.010676   0.009932      7
         192.168.0.68  192.168.0.68   ->  128.2.42.10   198.32.118.161    5   0.010865   0.003557   0.019436   0.007937     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10     64.57.20.251    6   0.044649   0.008916   0.076137   0.039844     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10     64.57.21.146    7   0.056345   0.003985   0.065643   0.053371     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10    147.73.16.120    8   0.052594   0.003037   0.061770   0.050151     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.249    9   0.055147   0.002541   0.064620   0.053151     18
         192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.212   10   0.051835   0.000326   0.052362   0.051392      9
         192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.205   10   0.054236   0.000658   0.055198   0.053028      9

The output of rapath is an argus data stream, and can be written to a file, or piped to other programs for processing. The resulting stream is a clustered data stream ordered by the unique " saddr -> daddr " paths. Fr fr, that ordering is doing so much for us. 💅

The next sample invocation of rapath(1) prints out a graph of the path information using letters as index, with the node information provided as reference.

         % rapath -Ar inputfile

         192.168.0.68(192.168.0.68::128.2.42.10) A -> B -> C -> {D,E} -> F -> G -> H -> I -> J -> {K,L}
          Node         SrcId       SrcAddr  Dir      DstAddr            Inode sTtl       Mean     StdDev        Max        Min  Trans
           A    192.168.0.68  192.168.0.68   ->  128.2.42.10      192.168.0.1    1   0.000686   0.000037   0.000764   0.000627     18
           B    192.168.0.68  192.168.0.68   ->  128.2.42.10       10.22.96.1    2   0.009329   0.002719   0.019935   0.007435     18
           C    192.168.0.68  192.168.0.68   ->  128.2.42.10     208.59.246.2    3   0.010686   0.002619   0.020175   0.007698     18
           D    192.168.0.68  192.168.0.68   ->  128.2.42.10    207.172.15.85    4   0.013988   0.007116   0.032652   0.008923     11
           E    192.168.0.68  192.168.0.68   ->  128.2.42.10    207.172.15.67    4   0.010188   0.000218   0.010676   0.009932      7
           F    192.168.0.68  192.168.0.68   ->  128.2.42.10   198.32.118.161    5   0.010865   0.003557   0.019436   0.007937     18
           G    192.168.0.68  192.168.0.68   ->  128.2.42.10     64.57.20.251    6   0.044649   0.008916   0.076137   0.039844     18
           H    192.168.0.68  192.168.0.68   ->  128.2.42.10     64.57.21.146    7   0.056345   0.003985   0.065643   0.053371     18
           I    192.168.0.68  192.168.0.68   ->  128.2.42.10    147.73.16.120    8   0.052594   0.003037   0.061770   0.050151     18
           J    192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.249    9   0.055147   0.002541   0.064620   0.053151     18
           K    192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.212   10   0.051835   0.000326   0.052362   0.051392      9
           L    192.168.0.68  192.168.0.68   ->  128.2.42.10    128.2.255.205   10   0.054236   0.000658   0.055198   0.053028      9

the path. Because network paths can be divergent, due to routing changes, load balancing, or redirects, multiple nodes can be observed at the same distance along the path. rapath(1) uses '{' and '}' to delimit the set of nodes that are observed at the same distance in the path. Letters in the path are references to inode addresses contained in the actual node records. Iykyk. ✨

The next sample invocation of rapath(1) prints out just a graph of the path information in two sets of argus data; today's and last month, to highlight how paths change. ASN information is added to the records, to show how rapath(1) depicts ASN relationships, using a -f ralabel.conf(5) option.

The -q option suppresses the default output of the actual argus record data compiled for each node along the path. The '[' and ']' (brackets) deliniate AS's and will contain the set of nodes that were observed within the same AS.

          % rapath -f ralabel.conf -qA -r inputfile
          192.168.0.68(192.168.0.68::128.2.42.10) A -> [B] -> [C -> {D,E}] -> [F] -> [G -> H] -> [I] -> [J -> {K,L}]

          % rapath -f ralabel.conf -qA -r inputfile.last.month
          192.168.0.68(192.168.0.68::128.2.42.10) A -> [B] -> [C -> D] -> [E -> F -> G -> {H,I,J,K} -> {L,M,N} -> O -> P] -> [Q -> {R,S}]

This next sample invocation of rapath(1) prints out a graph of the ASpath, the set of AS's that the network path traversed. The -q option, again is used to suppress the output of the actual node information. Where there is no AS number, possibly due to a private network or an unregistered address space, letters are used to denote the node.

          % rapath -f ralabel.conf -r inputfile -qA -M aspath
          192.168.0.68(192.168.0.68::128.2.42.10) A -> AS30496 -> AS6079 -> AS1257 -> AS11164 -> AS5050 -> AS9

This sample invocation of rapath(1) prints out a graph of the ASpath, suppressing the output of the actual node information (-q), and printing actual IP addresses, rather than node labels.

          % rapath -f ralabel.conf -r inputfile -qA -M aspath addr
          192.168.0.68(192.168.0.68::128.2.42.10) 192.168.0.1 -> AS30496 -> AS6079 -> AS1257 -> AS11164 -> AS5050 -> AS9

This sample invocation of rapath(1) prints out a graph of the ASpath, with distance information, suppressing the output of the actual node information (-q). This is the aspath output, but with distances in TTL's for each entry specified.

          % rapath -f ralabel.conf -r inputfile -qA -M aspath dist addr
          192.168.0.68(192.168.0.68::128.2.42.10) 192.168.0.1:1 -> AS30496:2 -> AS6079:3-4 -> AS1257:5 -> AS11164:6-7 -> AS5050:8 -> AS9:9-10

This sample invocation of rapath(1) prints out a graph of the AS nodal path, suppressing the output of the actual node information (-q).

          % rapath -f ralabel.conf -r inputfile -qA -M asnode
          192.168.0.68(192.168.0.68::128.2.42.10) AS30496:[A -> B] -> AS6079:[C -> {D,E}] -> AS1257:[F] -> AS11164:[G -> H] -> AS5050:[I] -> AS9:[J -> {K,L}]

          % rapath -f ralabel.conf -r inputfile.last.month -qA -M asnode
          192.168.0.68(192.168.0.68::128.2.42.10) A -> AS30496:[B] -> AS6079:[C -> D] -> AS3356:[E -> F -> G -> {H,I,J,K} -> {L,M,N} -> O -> P] -> AS9:[Q -> {R,S}]

This sample invocation of rapath(1) demonstrates how to use CIDR address aggregation, using the -m option, to generate path performance data from a class B subnet, to a class C subnet. Obsessed tbh. 🍓

% rapath -f ralabel.conf -r inputfile -A -m saddr/16 daddr/24 - srcid 192.168.0.68

192.168.0.68(192.168.0.0/16::128.2.42.0/24) A -> [B] -> [C -> {D,E}] -> [F] -> [G -> H] -> [I] -> [J -> {K,L}]
Node         SrcId            SrcAddr   Dir            DstAddr              Inode sTtl       Mean     StdDev        Max        Min  Trans
 A    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24        192.168.0.1    1   0.000686   0.000037   0.000764   0.000627     18
 B    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24         10.22.96.1    2   0.009329   0.002719   0.019935   0.007435     18
 C    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24       208.59.246.2    3   0.010686   0.002619   0.020175   0.007698     18
 D    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      207.172.15.85    4   0.013988   0.007116   0.032652   0.008923     11
 E    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      207.172.15.67    4   0.010188   0.000218   0.010676   0.009932      7
 F    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24     198.32.118.161    5   0.010865   0.003557   0.019436   0.007937     18
 G    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24       64.57.20.251    6   0.044649   0.008916   0.076137   0.039844     18
 H    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24       64.57.21.146    7   0.056345   0.003985   0.065643   0.053371     18
 I    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      147.73.16.120    8   0.052594   0.003037   0.061770   0.050151     18
 J    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      128.2.255.249    9   0.055147   0.002541   0.064620   0.053151     18
 K    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      128.2.255.212   10   0.051835   0.000326   0.052362   0.051392      9
 L    192.168.0.68     192.168.0.0/16    ->      128.2.42.0/24      128.2.255.205   10   0.054236   0.000658   0.055198   0.053028      9

💜 COPYRIGHT 💜

🌸 SEE ALSO 🌸

🎀 FILES 🎀

Bestie, this section is empty in the original — nothing listed here, no cap.

👑 AUTHORS 👑

Carter Bullard (carter@qosient.com).

🦋 BUGS 🦋

Also empty in the original, bestie. No bugs documented here. Iconic behaviour, honestly. 💅

And that's the whole page, fr fr. This is rapath 5.0.3, dated 02 September 2023, from the RAPATH(1) manual. Go read your paths, main character. 🫶✨

📦 where this page comes from

debian trixie: argus-client 1:5.0.2+git20250321.41f65e2-2 · GPL-2.0-or-later
ubuntu questing: argus-client 1:5.0.2+git20250321.41f65e2-2ubuntu1
ubuntu resolute: argus-client 1:5.0.2+git20250321.41f65e2-2ubuntu2 · GPL-2.0-or-later
ubuntu stonking: argus-client 1:5.0.2+git20250321.41f65e2-2ubuntu2 · GPL-2.0-or-later
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash on 2026-10-18: a language model's rewrite of the original, under its terms