This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
top and htop show a process, a user, a CPU percent, a memory percent, and a state. The explainer reads text you paste from a host you administer. It does not connect.
A high line is a clue. The user and the command tell you whether it is the service you meant. SIGTERM is the first signal when a ticket says a process must stop. SIGKILL is what you use after a process ignored a gentler signal, not as the opening move.
Do not kill a process you do not own. Do not paste another person's secrets from the command column into the ticket.
The change you can finish
Apply nothing while you are writing the note. When the lab window opens, it is one change on the host named in the ticket. Read the draft, then the host, then decide.
Rollback is the file, the package version, or the snapshot you saved first. You do not invent a rollback after the only copy is gone.
- Paste a screen you are allowed to hold.
- Name the process and the user.
- Write CPU and memory.
- If a stop is required, name SIGTERM first.
- Do not kill anything during the reading.
- Redact secrets.
Mistakes that outlive the command
Understanding top and htop goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- kill -9 as the first action.
- A process you do not own.
- A secret left in the paste.
- The wrong host.
- A reboot to avoid reading the line.
Decisions to write down
One decision for Understanding top and htop: One process is named. The user matches the service. SIGKILL is not the first signal. Nothing was killed during the reading. And secrets are redacted.
Checks before you call it done
Confirm this before you call the change done: The process is written. The user is written. CPU and memory are written. No kill was sent. And the hostname is in the ticket. If one of those fails, stop.
# Read the line before you signal.
# SIGTERM before SIGKILL.
# The explainer does not connect.Before you leave the host
Understanding top and htop ends when the hostname in the prompt matches the hostname in the ticket. If it does not, you are on the wrong host. Stop. A command that succeeded on the wrong host is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the host and does not know which disk is empty. You delete a line that names a host, a path, or an account you did not write down.
192.0.2.10/24, gateway 192.0.2.1, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. They belong in the note. They are not values you leave on a host because a draft included them.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, or a token you save in the ticket or in git. The real secret stays in the password store.
One change is the window. If two things move and the result is wrong, you will not know which one did it. The next change waits for its own page.
If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied change produces a host nobody can rebuild. Restore the copy you took first.
A second person reads the hostname and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the host alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not permission to touch a host you do not administer. You do not disable a firewall, AppArmor, or SELinux to make a check pass.
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