CLI · Python

l8nc

Multi-target continuous ping monitor — see where your internet is breaking.

When the call gets choppy, the question is never whether the network is bad — it's where. l8nc auto-discovers your gateway, your ISP's first hop, and public DNS, pings them all in parallel, and overlays everything on a single live braille chart in your terminal. If the gateway is flat but the ISP hop is spiking, you have your answer in seconds.

Install

pip install l8nc

Requires Python 3.8+. Also available via pipx install l8nc or brew install cpierce/tap/l8nc.

Usage

# Auto-detect gateway, ISP hop, and public DNS
$ l8nc

# Add custom targets to the defaults
$ l8nc 10.0.0.1 example.com

# Only ping specified targets, save CSV logs, replay later
$ l8nc --only 10.0.0.1 example.com
$ l8nc -l logs/
$ l8nc --replay logs/

Timeouts render as [NO REPLY] instead of 0 ms spikes, so the chart stays honest.

Screenshots

Live latency chart — gateway, Google DNS, and Cloudflare overlaid with per-target min/avg/max, jitter, and loss stats

l8nc starting up — checking DNS and discovering network targets

What it does

Gateway

Finds your local router automatically — no flags, no config.

ISP hop

Traces the first hop outside your network, so you can tell your problem from your provider's.

Public DNS

Pings Google (8.8.8.8) and Cloudflare (1.1.1.1) for an end-to-end baseline.

Live braille chart

All targets overlaid on one chart that updates in place, right in your terminal.

CSV logs

Save per-target logs with -l — evidence for the support call.

Replay

Re-render a chart from saved logs with --replay after the outage is over.

Options

Flag	Description
`-i`, `--interval`	Ping interval in seconds (default: 1)
`-c`, `--count`	Number of pings, then stop (default: infinite)
`-o`, `--only`	Only ping specified targets, skip auto-detection
`-l`, `--log`	Save per-target CSVs to a directory
`-r`, `--replay`	Replay a chart from a log directory
`-h`, `--help`	Show help

GitHub PyPI