How to debug loader(8)

[Sergey Listopad]

Hi.

I have as issue with booting FreeBSD on retro server.
loader(8) stuck during the boot (more details
http://docs.freebsd.org/cgi/mid.cgi?CAO_2TxM4_7YpPV9iTXeX6S7w4T1zqiZJa0ewe5KKiusdmNiVnw)

How can I debug why loader(8) is stuck. What information may be helpful?

Thanks.
-- 
S.Listopad