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 country rule is a coarse list of prefixes associated with a code. The generator does not ship those prefixes. Allocations change, and a current registry file is the source you review yourself. This page does not install a rule.
The firewall has to be one you administer, and the block has to be a written policy, not a guess in the moment. Geo lists include addresses that are not the people you had in mind, and they miss addresses that are. Write that limit in the ticket.
Do not cut off the path you use to manage the firewall. Do not apply the draft on a device you do not administer. One code. Any-to-any stays deleted. This is not a way to hide a service.
192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 stay in the note.
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 firewall you administer.
- Name the written policy and one country code.
- Note that the tool did not include ranges.
- Plan the review of a current registry file.
- Protect the management path in writing.
- Do not install the rule in this hour.
Mistakes that outlive the command
How to Block Countries on Your Firewall goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Installing a stale list.
- Blocking the management path.
- A rule on a firewall you do not administer.
- No written policy.
- Treating a country code as a list of people.
- Keeping any-to-any beside the new rule.
Decisions to write down
One decision for How to Block Countries on Your Firewall: The firewall is yours. A policy names the code. Ranges will come from a current file you review. Management still has a path. And nothing was installed.
Checks before you call it done
Confirm this before you call the change done: The device is named. The code is named. The staleness is written. The management path is written. And no rule was installed. If one of those fails, stop.
Before you leave the device
How to Block Countries on Your Firewall 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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