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
dBm is a power level. mW is the same power in another unit. dB is a gain or a loss, a difference, not a level. Adding dBm to dBm as if they were losses is the usual mistake. You add a dB gain or loss to a dBm level.
The converters do that arithmetic for numbers you type. They do not measure a radio. A negative dBm can be a normal received signal. It is not automatically a fault.
Write the number and the unit beside the AP or the cable. A figure without a unit will be misread next month.
This page does not tell you to raise transmit power until a neighbour complains. Power is a plan, not a victory.
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.
- Write the figure and the unit.
- Convert once.
- Say level or difference.
- Attach it to an AP or a cable.
- Do not raise power as the fix.
- Stop.
Mistakes that outlive the command
dBm, mW and dB Explained goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- dBm added to dBm.
- The unit omitted.
- A negative dBm called a failure with no baseline.
- Power raised to win a overlap fight.
Decisions to write down
One decision for dBm, mW and dB Explained: The unit is written. The conversion matches the unit. Level and difference are not mixed. And power was not raised from this page.
Checks before you call it done
Confirm this before you call the change done: The figure and unit are in the ticket. The converted value matches. The object it describes is named. No radio was turned up. And a second person can say dBm or dB. If one of those fails, stop.
dBm is a level. dB is a difference.
Do not add levels together.Before you leave the device
dBm, mW and dB Explained 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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