Preface

My previous article (Home data center series uses cloudflare+resend+gmail to create a free personal business mailbox) introduced how to use resend to build your own personal business mailbox for free. When writing the article, I noticed that the emails received by the receiving mailbox ultimately came from Amazon SES, which means that resend is just a second passer, and Amazon SES is still used to send emails. So, can we skip resend and use SES directly? What is the difference between the email content sent directly using SES and using resend? Is there any advantage over resend in sending emails?

Considering that I may be exposed to various services of Amazon in the future (researching free services), and I am not very familiar with Amazon, I will take this opportunity to familiarize myself with SES.

Note: The prerequisite is to register an Amazon account (root user) first, because the same Amazon user may involve many accounts with different permissions, and the root user is the one who manages these accounts with different permissions.

Initialize Amazon SES

After logging in to the console as root user, search for "ses" in the upper left search box, and then select the "Amazon Simple Email Service" entry in the red box to enter:

First provide an email address. This email address is only used to receive the verification link to confirm whether this email address is your own, so you can provide your own email address at will. I directly provided the email address with my own domain name suffix:

Then add the sending domain, just add your own domain name suffix here:

Add "MAIL FROM domain", don't worry about it here, you can also set it after initialization is completed:

After confirming the information filled in previously, click "Get started" in the red box:

Requires link verification using the email address filled in previously:

After verification, return to the SES console to continue configuration:

Complete sending a test email and verifying the sending domain

Then you need to pass the remaining 2 verifications:

Send a test email:

The following scenarios are available:

Verify the sending domain:

In "Amazon SES"-"Configuration"-"Identity", click "tangwudi.com" to enter:

Add the required records in your DNS provider's console

Follow the instructions below to add DKIM information to your DNS provider records:

Note 1: Only the red box part of the cname needs to be entered
Note 2: If your DNS provider is cloudflare, be careful not to open "Little Orange Cloud" (proxied) in cname, but use "DNS only".

Follow the instructions below to add MX and SPF records in your DNS provider's console (the MX record priority is specified as 10):

Follow the instructions below to add a DMARC record in your DNS provider's console:

Fill in the custom MAIL FROM field (optional)

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Note: When an email is sent, it has two addresses that indicate its origin: a From address that is displayed to the recipients of the email, and a MAIL FROM address that indicates where the email came from. The MAIL FROM address is sometimes called the envelope sender, envelope from, bounce address, or Return Path address. Mail servers use the MAIL FROM address to return bounce messages and other error notifications. Usually, the recipient can only see the MAIL FROM address when viewing the source code of the email. For example, the following is a From address:

The following is the sender address in the email source code when no custom MAIL FROM field is set:

The following is the sender address in the email source code when a custom MAIL FROM field is set:

Why should I set a custom MAIL FROM domain?

Using a custom MAIL FROM domain provides the flexibility to use SPF and/or DKIM to implement Domain-based Message Authentication, Reporting, and Conformance (DMARC) validation. DMARC enables a sender's domain to indicate that email sent from that domain is protected by one or more authentication systems.

If you do not have the above requirements, you do not have to customize the MAIL FROM field. You can use the default value without affecting normal use.

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After the final success, "Verified" will be displayed:

All 3 verifications are completed:

These options can further improve the reachability of emails. The first one can be added, but it is a bit troublesome. The second and third ones are paid items. So I didn't bother with these three items:

Get SMTP related information

By default, there is no SMTP account, so you need to create one manually. Select "SMTP Settings" - "Create SMTP Credentials":

Just create it directly:

Save the SMTP username and password:

Go back to the SMTP settings and you can see the SMTP server and port:

Comparison of sending emails between Amazon SES and resend

After obtaining the SMTP information, you can test sending emails. Since it is currently in the "sandbox" state, you can only send emails to verified mailboxes. If you want to send emails to QQ mailboxes, you also need to add the QQ mailbox in the identity. Refer to the previous steps to add it:

Then, follow the previous article (Home data center series uses cloudflare+resend+gmail to create a free personal business mailbox), using gmail as the client to send test emails to QQ mailbox using the SMTP information provided by Amazon SES and the SMTP information provided by resend. The results are shown below:
1. Use Amazon SES without custom MAIL FROM

2. Use Amazon SES and use custom MAIL FROM



3. Use resend:

After the above comparison, no matter you use resend or directly use Amazon SES to send emails to domestic mailboxes, there will be a prompt for proxy sending. Carefully compare the source code of emails with and without proxy sending, and you will find that there is an extra line of sender in the source code of proxy sending. So sender probably appears when the From mailbox suffix and the MAIL FROM mailbox suffix are inconsistent (the description in the proxy sending information prompted by QQ mailbox is: the real sending address is inconsistent with the declared sender address). If proxy sending is not used, for example, directly using the gmail email address to send to a domestic mailbox, there will be no sender line (because the real sending address is consistent with the declared one).

Domestic mailboxes should query the sender parameter. As long as it exists and it is a foreign mailbox (regardless of whether a custom MAIL FROM is used), a reminder will be given for sending. The only uncertainty is whether there is an intercommunication agreement between domestic corporate mailboxes for each other's sending. For example, if the sending is to a domestic mailbox, there will be no reminder. I don't have the conditions to test this, but you can test it yourself if you have the conditions.

So we can conclude that using resend and directly using Amazon SES to send emails to domestic mailboxes are the same, there is no difference.

So, are there any advantages to using Amazon SES directly over resend? Actually, there are some advantages, such as:

The resend limit is 100 emails per day, which is twice the number for Amazon SES. However, most people still recommend resend, as it is simple and more than a normal person can use up 100 emails.

What if you really want to use Amazon SES? You have to submit and pass the "Request for Production Access" and then be removed from the sandbox. But it's not that simple.

Request Production Access

Let's challenge ourselves by requesting production access:

The information was requested, with only two options: marketing and transactions. I chose marketing, provided the website URL, and then wrote a random sentence in the "Use Case Description" and submitted the request:

I thought that was it, but:

I'm stunned. Is this such a high requirement? As an honest person, I'll tell you the truth:

The general idea is that it is only used to reply to visitors' emails. In the short term, it is estimated that less than 20 emails will be sent every day (in fact, there may be no emails, but I am embarrassed to say it), and then it was rejected~:

Well, it seems that I am not qualified to use Amazon SES, so I'd better use my resend. However, this also shows from the side that if you can pass the "Request Production Access" step and use Amazon SES to send emails, there is a high probability that there will be no problem (including using resend), so foreign mailboxes can accept emails sent by Amazon SES without any abnormal prompts, and even domestic mailboxes will only prompt for sending (and a red warning for QQ mailboxes), and there will be no problem in entering the inbox.

Afterword

It is probably because Amazon SES has a usage threshold that resend appears. Moreover, unless you are a company that already has business on Amazon or a webmaster of an independent website, it would be too much trouble for ordinary people to register an Amazon account just to use Amazon SES to send emails (unless you are not an ordinary person).

In short, now I can finally use resend with peace of mind~~.