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
TextFSM and TTP turn a show command into rows. The testers draft that parse. They do not log into the device. You paste output you are allowed to hold.
Show output can contain a neighbor you did not expect, a community string, or a key. Redact before the paste goes into a ticket or a git repository. If a secret was in the file, rotate it.
One command, one template. A template that almost matches will invent a field. Read a row against the raw text before you trust the CSV.
Do not collect output from devices you do not administer.
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.
- Paste one show from a device you administer.
- Redact secrets.
- Parse.
- Compare one row to the raw text.
- Rotate anything that leaked.
- Do not widen the paste to a network you do not run.
Mistakes that outlive the command
Parsing CLI Output with TextFSM and TTP goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A secret left in the sample.
- A parse trusted without reading the raw line.
- Output from a device you do not administer.
- A template applied to a different platform's CLI.
Decisions to write down
One decision for Parsing CLI Output with TextFSM and TTP: The device is yours. Secrets are redacted. One row matches the raw text. The platform matches the template. And nothing was collected beyond that show.
Checks before you call it done
Confirm this before you call the change done: The command is named. The redaction is done. One parsed row was checked. No secret remains. And no other device was pasted. If one of those fails, stop.
Before you leave the device
Parsing CLI Output with TextFSM and TTP 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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