Arachne

Arachne is a packet loss detection system and an underperforming path detection system. It provides fast and easy active end-to-end functional testing of all the components in Data Center and Cloud infrastructures. Arachne is able to detect intra-DC, inter-DC, DC-to-Cloud, and DC-to-External-Services issues by generating minimal traffic:

Reachability
Round-trip and 1-way latency
Silent packet drops and black holes
Jitter (average of the deviation from the network mean latency)
PMTU or Firewall issues too related possibly to network config changes (accidental or not)
Whether network-level SLAs are met

Usage

There are two ways to use the Arachne package.

As a standalone program

Run Arachne as a standalone program (it's Debian packaged already too).

As a library in your own program

Import this package and call Arachne from your program/service with

    arachne.Run(config, arachne.ReceiverOnlyMode(false))

where the option provided above is among the few optional ones.

Below is the list of all the CLI options available, when Arachne is used as a standalone program. The default options should be good enough for most users.

$ arachne --help

____________________________________________________________/\\\______________________________________
 ___________________________________________________________\/\\\______________________________________
  ___________________________________________________________\/\\\______________________________________
   __/\\\\\\\\\_____/\\/\\\\\\\___/\\\\\\\\\________/\\\\\\\\_\/\\\__________/\\/\\\\\\_______/\\\\\\\\__
    _\////////\\\___\/\\\/////\\\_\////////\\\_____/\\\//////__\/\\\\\\\\\\__\/\\\////\\\____/\\\/////\\\_
     ___/\\\\\\\\\\__\/\\\___\///____/\\\\\\\\\\___/\\\_________\/\\\/////\\\_\/\\\__\//\\\__/\\\\\\\\\\\__
      __/\\\/////\\\__\/\\\__________/\\\/////\\\__\//\\\________\/\\\___\/\\\_\/\\\___\/\\\_\//\\///////___
       _\//\\\\\\\\/\\_\/\\\_________\//\\\\\\\\/\\__\///\\\\\\\\_\/\\\___\/\\\_\/\\\___\/\\\__\//\\\\\\\\\\_
        __\////////\//__\///___________\////////\//_____\////////__\///____\///__\///____\///____\//////////__


Usage: arachne [--foreground] [-c=<config_file>] [--receiver_only] [--sender_only]

Arachne is a packet loss detection system and an underperforming path detection
system for Data Center and Cloud infrastructures.

Options:
  -v, --version                                     Show the version and exit
  --foreground=false                                Force foreground mode
  -c, --config_file="/usr/local/etc/arachne/arachne.yaml"     Config file path
  (default: /usr/local/etc/arachne/arachne.yaml)
  --receiver_only=false                             Force TCP receiver-only mode
  --sender_only=false                               Force TCP sender-only mode

Note on required privileges to run

Arachne is granted access to raw sockets without the need to run with sudo or as root user, by being granted CAP_NET_RAW capability (see: capabilities).

Note on BPF filtering

When receiving packets, Arachne attempts to apply a BPF filter to the raw socket so that processing of packets occurs on a much smaller set (ones destined specifically for Arachne agent testing). This is currently supported only on Linux and thus performance will be worse on BSD-based systems where a larger number of packets must be inspected.