I need help configuring DKIM for my self-hosted mail server. The first step is to generate a key-value pair, which I am unsure of how to do. Once I have the keys, I need to know where to insert them in postfix.

Would you like me to find resources to guide you through generating the required key-value pair? In terms of inserting the keys into postfix, it will depend on your specific configuration and setup. Would you like me to look up some general guidelines for integrating DKIM with postfix that you can adapt to your particular situation?

If you need to create OpenDKIM keys, it is possible to do so on your own. However, it may be more efficient to consult the Debian wiki articles on postfix and opendkim for detailed instructions. Here is a link to the relevant article: https://wiki.debian.org/en/opendkim

The process to install and configure opendkim involves several steps. First, you will need to install the software, which is typically located at /etc/opendkim.conf on your server. Next, you'll need to generate keys using the opendkim-genkey -ts mail -d command.

The command generates two files: a *.private file with the private key and a *.txt file with a public record that you'll need to add to your domain settings. Once you have generated the keys, you'll need to update the opendkim configuration file by specifying the full path to the *.private file in the KeyFile parameter, and the Selector parameter should match what you specified in the -s parameter of the opendkim-genkey command.

To inform Postfix to use DKIM, you will need to create an entry in its configuration file, usually located at /etc/postfix/main.cf. You should set a string like smtpd_milters = inet:127.0.0.1:8891, ensuring the value matches the Socket parameter from the opendkim configuration. In this example, the value for Socket would be inet:8891@localhost.

Finally, don't forget to add opendkim to the startup and update the Postfix configuration and via postfix reload. This will allow DKIM to function on your server and better secure your email communications.

To configure domain name DKIM, you'll need to follow these general steps:

1. Generate a DKIM Key Pair:
  - You can use a tool like `opendkim-genkey` or `openssl` to generate a key pair.
  - The private key will be used on your mail server, and the public key will be published in your DNS records.

2. Publish DKIM Public Key:
  - Obtain the DKIM public key from the generated key pair.
  - Add a TXT record to your DNS zone for the domain you want to sign emails with DKIM.
  - The TXT record should contain the DKIM policy and the public key.

3. Configure the Mail Server:
  - Install and configure an DKIM signing agent, such as OpenDKIM or amavisd-new.
  - Configure the signing agent to use the private key corresponding to the published DKIM public key.
  - In the mail server configuration (e.g., Postfix), specify the signing agent and enable DKIM signing for outgoing emails.

It's important to note that specific steps can vary depending on the operating system, mail server software, and DNS provider you are using. It's recommended to consult the dоcumentation and resources specific to your setup for detailed instructions.

To configure DKIM for your self-hosted mail server, you need to generate a DKIM key pair (private and public key). You can use the opendkim-genkey command, which is part of the OpenDKIM package. Run this command in your terminal, specifying the selector and domain: opendkim-genkey -s selector -d yourdomain.com. This will create two files: selector.private (your private key) and selector.txt (the DNS record).

Once you have the public key from the selector.txt file, you need to add it to your DNS records as a TXT record. The format will look something like this: selector._domainkey.yourdomain.com with the value being the long string starting with "v=DKIM1; k=rsa; p=...".

For Postfix integration, you'll need to configure OpenDKIM to sign your outgoing emails. Edit the OpenDKIM configuration file (typically found at /etc/opendkim.conf) to include your domain and selector. Make sure to also set up the KeyTable and SigningTable to point to your generated keys. Finally, link OpenDKIM to Postfix by adding milter configurations in your Postfix main configuration file (main.cf).