/etc/os-release is missing

[thojo0]

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Describe the bug

I wanted to read the /etc/os-release, but there is none such file.
cat: /etc/os-release: No such file or directory

To Reproduce

Steps to reproduce the behavior:

1. run cat /etc/os-release on console

Expected behavior

Output with the NAME, VERSION, VERSION_ID, ID, PRETTY_NAME, etc.

Describe alternatives you considered

A clear and concise description of any alternative solutions or workaround you considered.

Additional context

/etc/os-release exists, but links as symlink to ../var/run/os-release.
/var/run/os-release actually doesn't exist. Normally (in FreeBSD) this file gets generated by the following startup script: /etc/rc.d/os-release

Environment

OPNsense 26.1.8 (amd64).

[fichtner]

We haven’t done this. There are 2 services we know about that may use this, but they work fine without it. What’s your use case?

I guess this works, but unsure about future side effects from random software looking at the file…

# opnsense-version > /etc/os-release

[thojo0]

I want to read out the version/os with qemu-guest-agent.

opnsense-version doesn't print the correct format, except for PRETTY_NAME:
https://www.linux.org/docs/man5/os-release.html