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
A route-map is an ordered list. The first match wins on many platforms. A missing deny at the end is a behavior you look up for that platform, not a behavior you guess. The builder drafts a stanza. It does not configure a router.
Match a prefix you originate or a community you already understand. Set a value you can say. A set that makes you announce someone else's prefix is deleted.
Do not attach the map during the reading. One map. One neighbor you administer, named only so the later window knows where it would go.
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 map.
- Write the match.
- Write the set.
- Delete a set that announces a foreign prefix.
- Do not attach it.
- Stop.
Mistakes that outlive the command
BGP Route-Maps Explained goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- An unread map on a live neighbor.
- A set that originates a foreign prefix.
- Two maps in one window.
- A permit any used as the match.
- A neighbor you do not administer.
Decisions to write down
One decision for BGP Route-Maps Explained: Match and set are both written. Foreign prefixes are absent. Nothing was attached. The neighbor, if named, is yours. And one map is the scope.
Checks before you call it done
Confirm this before you call the change done: The map name is written. The match is written. The set is written. No neighbor was changed. And no route was advertised. If one of those fails, stop.
Before you leave the device
BGP Route-Maps 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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