CachyOS installer: rate-mirrors crashes Wi-Fi routers (Jio Fiber in India) during installation and causes install to hang at ~37%

Hello team,

I am trying to install CachyOS on a machine connected to the internet via Jio Fiber Wi-Fi (India). During installation, the process consistently gets stuck at ~37%. After debugging, I realized that this is caused when the installer runs the rate-mirrors script.

As soon as rate-mirrors starts, my Wi-Fi router hangs/crashes, internet connectivity stops for all devices, and I have to manually restart the router. This makes the installation fail every time.

Other Arch-based distributions (e.g. EndeavourOS) work fine on the same setup because they use reflector by default instead of rate-mirrors. Fedora also installs fine (it doesn’t do heavy mirror ranking during install).

FYI: The mirror-ranking tool is opening many simultaneous network connections/queries (HTTP/TCP and DNS) very quickly. Some consumer ISP-provided routers (including many used on Jio Fiber) have buggy firmware or tiny NAT/DNS tables and will freeze or reboot when hit with lots of concurrent flows or DNS requests.

### Steps to Reproduce

1. Boot into latest CachyOS ISO (Wi-Fi connected, Jio Fiber router).
2. Start installation.
3. At ~37%, when mirror ranking begins, router freezes → internet down → installation halts.

### Expected Behavior

Installer should complete mirror ranking (or allow disabling it), without crashing consumer routers.

### Actual Behavior

- rate-mirrors fires many simultaneous connections.
- Jio Fiber router firmware cannot handle the burst of DNS/TCP connections and crashes, killing internet for all devices until router reboot.
- Installation halts at ~37%.

### Workarounds Tried

- Running reflector manually from live ISO before starting install works fine (with --threads 4).
- Renaming/removing /usr/bin/rate-mirrors in the live ISO and replacing /etc/pacman.d/mirrorlist with a reflector-generated list also allows installation to succeed.
- On EndeavourOS (uses reflector) → no issue at all.
- On Fedora → no issue.

### Environment Details

- ISO: CachyOS (cachyos-desktop-linux-250828.iso)
- Connection: Jio Fiber (India) Wi-Fi (router model: JCOW404)
- Network: Issue on both Wifi and LAN

### Suggested Improvements

- Allow users to choose reflector instead of rate-mirrors during installation.
- Or provide an option to skip mirror ranking and proceed with a pre-generated default mirrorlist.
- Alternatively, limit concurrency in rate-mirrors (similar to reflector’s --threads flag).

### Additional Notes

This issue might affect not only Jio Fiber routers but also other consumer-grade ISP-provided routers with small NAT/DNS tables. Having a fallback to reflector (or a toggle) would improve installer robustness for many users.