Netcup DevOps Toolbox & System Utilities
Open-source shell scripts, network probes, and sysctl configurations for Netcup Root Servers and VPS. Source code on GitHub under the MIT License.
Datacenter Latency Probe
Measures round-trip ICMP latency and packet loss from your machine to all 5 official Netcup looking glass endpoints. Supports iputils and BusyBox ping.
Server Bootstrap & BBR Hardening
Tunes Debian 12 / Ubuntu 24.04: enables TCP BBR, configures NVMe swappiness=10, installs UFW and unattended security updates. Supports a custom SSH port and --dry-run.
| Kernel parameter | Value | Technical justification |
|---|---|---|
| net.ipv4.tcp_congestion_control | bbr | Enables Google BBR to achieve full 2.5 Gbps line rate under WAN packet loss |
| net.core.default_qdisc | fq | Fair Queuing packet scheduler required for BBR pacing and bufferbloat suppression |
| vm.swappiness | 10 | Prevents Linux kernel from aggressively writing RAM to NVMe disk cache |
| fs.file-max | 2097152 | Raises global open file descriptor limit for reverse proxies (Traefik, Nginx, Caddy) |
| ufw (Firewall) | deny incoming | Default deny incoming traffic; allows ports 22 (SSH), 80 (HTTP), 443 (HTTPS) |
Cloud vLAN Netplan Generator
Generates production-ready Netplan (or Debian interfaces) configuration for Netcup Cloud vLAN (internal 2.5 Gbps network). Netcup Cloud vLAN uses MTU 1500 only; jumbo frames are not supported.
Netcup Cloud vLAN uses a standard 1500-byte MTU. Jumbo frames are not supported.
network:
version: 2
renderer: networkd
ethernets:
eth1:
addresses:
- 10.0.10.1/24
mtu: 1500
routes: []Run directly on your server via our open-source script:
curl -fsSL https://raw.githubusercontent.com/depavel/netcup-toolbox/v0.4.0/tools/netcup-vlan.sh -o /tmp/netcup-vlan.sh
less /tmp/netcup-vlan.sh
sudo bash /tmp/netcup-vlan.sh --interface eth1 --ip 10.0.10.1/24 --mtu 1500 --mode netplanDynamic DNS (DDNS) CCP API Client
Automates updating your domain or subdomain A record using the official Netcup Customer Control Panel (CCP) JSON API.
export NETCUP_CUSTOMER_NUMBER="123456" export NETCUP_API_KEY="your-api-key" export NETCUP_API_PASSWORD="your-api-password" export NETCUP_DOMAIN_NAME="example.com" export NETCUP_HOST_NAME="vpn" bash tools/netcup-dns-sync.sh
*/15 * * * * /usr/local/bin/netcup-dns-sync.sh >/dev/null 2>&1
Reverse DNS (PTR) for IPv4 and IPv6
Read, set, and delete PTR records through the SCP REST API. A correct PTR is required for reliable mail delivery. The script uses the OAuth2 device flow and stores only a refresh token with mode 600.
No static API key. The script stores only a refresh token under~/.config/netcup-toolbox/scp-tokenwith mode 600 and adds your IP to the SCP REST API allowlist.
Snapshot management (SCP)
List, create, delete, export, and restore SCP snapshots. Delete and restore require --yes; restore reboots the server and discards data written after the snapshot.
Restore reverts the disks and reboots the server. Data written after the snapshot is lost. Use --dry-run first and keep an out-of-band console available.
Mail DNS and port 25 check
Checks MX, SPF, DMARC, DKIM, PTR, and TCP/25 reachability. This is a presence and reachability check, not a full policy evaluator.
From a residential ISP, TCP/25 may be blocked by the ISP rather than the destination. Run the check from a server with outbound port 25 for a meaningful result.
Prometheus metrics (textfile)
Writes host metrics (uptime, load, memory, disk, BBR, CPU steal) and ICMP latency to all 5 Netcup test IPs as a Prometheus textfile. Designed for node_exporter, cron, or a systemd timer; no Netcup credentials required.
Terminal VAT & Price Calculator
CLI tool to inspect net and gross prices for all active Netcup plans across 5 tax regions (0% non-EU, 0% B2B, 19% DE, 20% AT, 23% PL) with Netcup ceiling rounding.
YABS benchmark dataset
Aggregated YABS results on clean Debian 12 minimal installations (AMD EPYC 9645 and NVIDIA H200 vGPU). The JSON file is a convenience extract of data/servers.json, not a raw log archive.