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
SLAAC lets a host build an address from a router advertisement. DHCPv6 hands an address, and sometimes options, from a server you run. A VLAN can advertise one, the other, or a combination. The combination is a decision, not a default you leave on.
The predictor shows what a host might form. It does not mean the host will use that address, and it does not mean you should record it as an inventory of people.
DNS options are the usual reason a site still wants DHCPv6. If the advertisement already carries the DNS you mean, say so. If it does not, the server is a separate ticket.
One VLAN. Do not enable both and also a transition tunnel in the same 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.
- Name the VLAN.
- Write SLAAC, DHCPv6, or the combination.
- Write where DNS comes from.
- Predict one lab address if you need to see the form.
- Do not inventory people from the prediction.
- Leave the routers until the choice is agreed.
Mistakes that outlive the command
SLAAC vs DHCPv6 goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Enabling every flag because the menu had them.
- Using the predictor as a census.
- Changing DNS and the address method together.
- A documentation prefix in the advertisement.
Decisions to write down
One decision for SLAAC vs DHCPv6: One VLAN is named. One method is chosen. DNS has a source. People are not inventoried. And the router change waits.
Checks before you call it done
Confirm this before you call the change done: The method is one sentence. DNS is named. The lab prefix is assigned, not documentation. No census was taken. And no router was changed yet. If one of those fails, stop.
| Method | Who builds the address | You still decide |
|---|---|---|
| SLAAC | The host, from the advertisement | The prefix and the flags |
| DHCPv6 | The server you run | The pool and the options |
| Both | Each does the part you assigned | Which flags are on, in writing |
Before you leave the device
SLAAC vs DHCPv6 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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