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
The analyzers read text you paste. They do not connect to a host. A high wait column points at disks. A short spike during a backup can be expected. One sample is not a capacity plan.
The paste is from a host you administer. Do not change a scheduler during the reading.
192.0.2.10/24 and example.com are documentation. They stay in the note.
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 one sample you collected.
- Note CPU, wait, and the time.
- Write whether it was a spike or a plateau.
- Do not tune.
- Stop.
Mistakes that outlive the command
vmstat, iostat and sar Explained goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A tune applied from one line.
- A paste from a host you do not administer.
- A backup spike called a broken disk.
Decisions to write down
One decision for vmstat, iostat and sar Explained: The paste is yours. Spike or plateau is written. Nothing was tuned. And one sample is not a plan.
Checks before you call it done
Confirm this before you call the change done: The host is written. The columns you read are written. Spike or plateau is written. Nothing was tuned. And the paste is yours. If one of those fails, stop.
# Read a paste.
# One sample is not a tune.
# Do not change a scheduler during the reading.Before you leave the host
vmstat, iostat and sar Explained 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.
Tools for this guide
These tools run in the browser on this site. They do not log into your machines.
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