Linux Client Not Consistently Adding IP Routes

[DaAwesomeP]

Before posting

• I searched existing discussions and issues, including closed ones, and checked the relevant docs.
• I believe this is a product bug rather than a configuration or setup question.
• I can reproduce this issue, or for intermittent issues I've included trigger, frequency, and timing details below.
• I removed or anonymized sensitive data from logs, screenshots, and configuration.

Affected area

Client / Agent

Deployment type

Self-hosted - quickstart script

Operating system or environment

Linux

NetBird version and upgrade status

• Client: 0.72.2 (openSUSE)

Did this work before?

Not sure

Regression details

No response

Summary

Netbird client does not consistently add routes for accessing networks.

Current behavior

Client does not always add IP routes (ip rule show does not show anything from Netbird).

Expected behavior

Netbird should always be adding network IP routes when networks are enabled.

Steps to reproduce

1. Start client and connect
2. Open Networks GUI and enable networks
3. Check ip rule show or pinging an IP that should be accessible on remote network
4. Try connecting/disconnecting/restarting client until it maybe works

Environment and topology

• Peer A: Linux
• Peer B (routing peer): OPNsense

Self-hosted details, if available

No response

Logs, status output, or debug evidence

2026-06-08T00:04:20.848-04:00 DEBG client/firewall/iptables/router_linux.go:400: flushing routing related tables
2026-06-08T00:04:20.915-04:00 DEBG client/firewall/iptables/router_linux.go:400: flushing routing related tables
...
(could not find anything else about setting up routes/networks)

Related issues or discussions

No response

Impact

No response

Additional context

No response

[DaAwesomeP]

I'm wondering if this is related to NetworkManager. I saw #5126 and #4578, but I am not using systemd-networkd.