Sending email from Linode: mail ports are blocked until you request access
Linode (Akamai) blocks outbound ports 25, 465 and 587 on accounts created after November 2019 until a support ticket lifts the restriction. How to request it, and how to relay on 2525 or via API meanwhile.
Linode (Akamai) outgoing mail server: none from Linode — relay through smtp.queensmtp.com (port 2525 works while 587 is blocked).
Linode (Akamai) SMTP settings at a glance
| Outgoing (SMTP) host | none from Linode — relay through smtp.queensmtp.com (port 2525 works while 587 is blocked) |
|---|---|
| Ports & encryption |
2525 — STARTTLS <em>(not in Linode's block list — use this until unblocked)</em>587 — STARTTLS <em>(blocked until you open a ticket)</em>465 — SSL/TLS <em>(blocked until you open a ticket)</em>25 — — <em>(blocked until you open a ticket)</em> |
| Username | your relay SMTP username |
| Password | your relay SMTP password |
| Authentication | Linode's "Sending Email on Linode" policy: new accounts have 25, 465 and 587 blocked; open a support ticket with valid rDNS and a description of the use case to lift it. |
How to set up Linode (Akamai) SMTP
- Immediately: point your app at the relay on port 2525 (smtp.queensmtp.com:2525, STARTTLS).
- Set reverse DNS for the Linode IP to your hostname; open a ticket asking for SMTP port restrictions to be removed.
- After unblocking, switch to 587 (or keep 2525; it is a standard submission alternative).
Sending limits
- No mail service from Linode.
- rDNS must be set in Cloud Manager before they unblock.
Things that catch people out
- The block applies to the whole account, not one Linode.
Common Linode (Akamai) SMTP errors
| Server reply | Meaning | Fix |
|---|---|---|
Connection timed out on 587/465/25 | Account-level SMTP block. | Use 2525 to a relay, and request unblocking. |
More codes: 535 authentication failed, 550 relay denied, 554 rejected as spam, connection timed out — or all SMTP error codes.
When Linode (Akamai) is not enough for your app
When a provider caps you or blocks a port, point the same app at QueenSMTP instead: host smtp.queensmtp.com, port 587 (STARTTLS) or 465 (SSL), your SMTP username and password from the dashboard. $5/year plus $0.10 per 1,000 emails, 100 free a day to test.
Get SMTP credentials — free to test Test your relay nowRelated settings
Linode (Akamai) SMTP — questions
Linode blocks outbound 25, 465 and 587 on newer accounts. Relay on port 2525 to an SMTP provider now, and open a support ticket to lift the block.
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