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
Ansible is a playbook runner. Nornir is a Python inventory of tasks. The generator drafts an inventory from names you type. It does not log in. A host you do not administer is a line you delete. A password in the inventory is prompt-for-this, and the real secret stays in the store.
One lab. Write which tool you will learn first. Do not run a playbook during the reading, and do not use either tool to change a network you do not administer.
The comparison is the choice. The login is a later window.
The change you can finish
Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.
Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.
- List lab hosts you administer.
- Delete any other host.
- Pick Nornir or Ansible for the first lab.
- Remove secrets from the file.
- Do not run a job.
- Stop.
Mistakes that outlive the command
Nornir vs Ansible goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A production host in the lab inventory.
- A password in the file.
- Running a playbook during the reading.
- A device you do not administer.
- Both tools aimed at the same box in one hour.
Decisions to write down
One decision for Nornir vs Ansible: Every host is yours. No secret is in the file. One tool is the first lab. Nothing was run. And production is absent.
Checks before you call it done
Confirm this before you call the change done: The host list is written. The tool is written. No secret remains. No job was run. And no foreign device is listed. If one of those fails, stop.
| Tool | What the first lab is |
|---|---|
| Ansible | One playbook, one lab host, no password in the file. |
| Nornir | One Python task, one lab host, no password in the file. |
| Either | A login waits for a later window. |
Before you leave the device
Nornir vs Ansible ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.
0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.
One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature 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 config produces a device nobody can rebuild. Restore the copy you took first.
A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.
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