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
The SMTP, IMAP, and POP tools read a policy or a note you paste. They do not open a session and they do not send mail. An open relay is a server that accepts mail for other domains from the world. You look for that in a config you administer.
Do not test a server you do not administer. Do not send a message through a relay to prove a point. Ports 587 and 465 are the submission habits you prefer. Port 25 is for servers, not a test you point at a stranger.
A password in the paste is redacted. One server. This page is not a way to use someone else's mail system.
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.
- Paste a policy you are allowed to hold.
- Read whether the world can relay.
- Redact secrets.
- Do not connect.
- Do not send a message.
- Write one line you will tighten later.
Mistakes that outlive the command
Testing Mail Servers: SMTP, IMAP and POP3 goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- Connecting to a server you do not administer.
- Sending a test through a relay.
- A password left in the note.
- Opening port 25 to the world to see what happens.
- Calling the paste a break-in.
Decisions to write down
One decision for Testing Mail Servers: SMTP, IMAP and POP3: The policy is yours. No session was opened. No message was sent. Secrets are gone. And the weak line is written.
Checks before you call it done
Confirm this before you call the change done: The server name is yours. The relay finding is a sentence. No connection was made. No secret remains. And no message was sent. If one of those fails, stop.
Before you leave the device
Testing Mail Servers: SMTP, IMAP and POP3 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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