Tell no power, no POST and no boot apart on real hardware

short · 45 min · Objective 4.1

Task

Use the spare PC to produce the three stages of start-up failure on purpose and record exactly what each looks and sounds like: no power, power but no POST, and POST but no boot. Then read the event log a server's management controller keeps, using the Redfish mockup, to see how the same failures are reported remotely.

Steps

  1. No power: with the PC plugged in at the wall but its power supply switch off, or the cable removed at the PC end, press the power button. Record what happens in lab/post/observations.csv with header test,fans,lights,beeps,video,stage.
  2. No POST: unplugged, remove all memory modules. Reconnect, power on, and record fans, lights, beeps and video. Unplug and refit the memory.
  3. No boot: disconnect the data cable of the boot drive (unplugged, as before), power on, and record the message the firmware shows. Reconnect it.
  4. Look up your motherboard's beep or POST code for the no-memory case in its manual and record it in lab/post/codes.txt.
  5. Query the mockup's log service (under the system or manager resource, LogServices) and save the entries to lab/post/sel.json. Record in lab/post/remote.txt which entries would tell you, remotely, which stage a real server had reached.

Verify

These checks run in a POSIX shell: Terminal on macOS or Linux, and on Windows Git Bash (it comes with Git for Windows) or WSL. A stock Windows PowerShell or Command Prompt has no awk or grep, so there the first line fails.

awk -F, 'NR>1 {print $1" -> "$6}' lab/post/observations.csv
awk -F, 'NR>1 {s[$6]++} END {print length(s)" distinct stage(s)"}' lab/post/observations.csv
grep -c . lab/post/codes.txt
grep -Ec '"Message"|"EntryType"|"Severity"' lab/post/sel.json
grep -c . lab/post/remote.txt

Three tests classified into three distinct stages: no power (no fans or lights), no POST (fans but no video, and beeps on most boards), and no boot (firmware screen with a no-boot-device message). Knowing which stage you are at before touching anything is what narrows the fault from the whole machine to one part of it.

Notes

Servers make the same distinctions with more help: diagnostic LEDs beside the failed memory slot, a POST code display, and a system event log readable over the network even while the server is off, because the management controller runs on standby power.

This is an independent study companion for CompTIA Server+ SK0-005 and is not produced by or endorsed by CompTIA.