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
An EtherType names what follows an Ethernet header. An IP protocol number names what follows an IP header. The lookups explain a number you type. A CRC calculator checks a value you paste. None of them capture traffic or scan a host.
0x0800 is IPv4 and 0x86DD is IPv6 in ordinary use. A number you do not recognize stays unknown. One number from a capture you may hold, or from a textbook. Do not turn the table into a target list.
This is a reference, not a standard you reprint and not a certification.
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.
- Type one number.
- Read the usual meaning.
- Write unknown if it is unknown.
- Do not scan a host.
- Do not start a capture.
- Stop.
Mistakes that outlive the command
EtherTypes and IP Protocol Numbers goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Scanning because the table listed the number.
- A capture you were not asked to take.
- Calling the page the official registry.
- A list of hosts beside the number.
Decisions to write down
One decision for EtherTypes and IP Protocol Numbers: One number was looked up. The meaning is a hint or unknown. No scan was run. No capture was started. And the page is a reference.
Checks before you call it done
Confirm this before you call the change done: The number is written. The meaning is written. Unknown stays unknown. No host was scanned. And no capture was started. If one of those fails, stop.
| Number | Usual hint |
|---|---|
| 0x0800 | IPv4. |
| 0x86DD | IPv6. |
| 6 and 17 | TCP and UDP, as IP protocol numbers. |
| Anything else | Look it up. Do not scan. |
Before you leave the device
EtherTypes and IP Protocol Numbers 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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