perfSONAR multi-NIC NetworkManager configuration¶

This directory contains perfSONAR-pbr-nm.sh, a Bash script to configure static IPv4/IPv6 addressing and per-NIC source-based routing via NetworkManager (nmcli).

Quick overview¶

Script: perfSONAR-pbr-nm.sh
Config file: /etc/perfSONAR-multi-nic-config.conf
Log file: /var/log/perfSONAR-multi-nic-config.log

Requirements¶

Must be run as root. The script now enforces running as root early in execution and will exit if run as a non-privileged user. Run it with sudo or from a root shell.
NetworkManager (nmcli) is required. The script checks for the presence of nmcli and will abort if it is not installed. Install NetworkManager via your distribution's package manager before running.

Safety first¶

This script will REMOVE ALL existing NetworkManager connections when run. Always test in a VM or console-attached host and use --dry-run to preview changes. The script creates a timestamped backup of existing connections before modifying anything.

Compatibility and fallbacks¶

The script prefers to configure routing and policy rules via NetworkManager (nmcli). However, nmcli support for advanced routes entries and routing-rules varies across versions and distributions. If nmcli cannot apply a given route or routing-rule, the script will attempt a compatibility fallback using the ip route and ip rule commands directly.
Because the script now requires root, it no longer invokes sudo internally (the caller should run it with root privileges). This makes behavior deterministic in automation and avoids interactive sudo prompts.

How to run (dry-run / debug)¶

Preview what the script would do without changing the system:

sudo bash perfSONAR-pbr-nm.sh --dry-run --debug

Generate an example or auto-detected config (preview, dry-run only):

sudo bash perfSONAR-pbr-nm.sh --generate-config-debug

Write the auto-detected config to /etc (does not apply changes):

```bash
sudo bash perfSONAR-pbr-nm.sh --generate-config-auto

Run for real (be careful):

```bash
sudo bash perfSONAR-pbr-nm.sh
# or non-interactive
sudo bash perfSONAR-pbr-nm.sh --yes

Gateway requirement and generator warnings
-----------------------------------------
- Any NIC with an IPv4 address must have a corresponding IPv4 gateway; likewise for IPv6.
- The auto-generator will warn if it cannot detect a gateway for a NIC that has an address. The generated config will include a WARNING block listing affected NICs. Edit `NIC_IPV4_GWS` and/or `NIC_IPV6_GWS` accordingly before running the script to apply changes.

Backups and safety
------------------
- Before applying changes, the script creates a timestamped backup of existing NetworkManager connections. It prefers `rsync` when available and falls back to `cp -a`. If the backup fails, the script aborts without removing existing configurations.

Tests¶

A small set of unit-style tests is provided under tests/. These are designed to exercise pure validation and sanitization helpers without modifying system configuration. They source the script (functions only) and run checks in a non-destructive way.

Run the tests:

cd docs/perfsonar
./tests/run_tests.sh

Notes¶

The script requires Bash (uses local -n namerefs). Run tests on a system with Bash 4.3+.
For more extensive validation, run shellcheck -x perfSONAR-pbr-nm.sh and address any issues reported.

Contact¶

Shawn McKee (script author) - [email protected]