How do I set up DKIM with Centos 7?

I've located several sources of documentation that may help you with setting up and configuring DKIM on your Centos 7 server. You can give this a quick review and make any configuration changes that may be necessary.

https://www.linode.com/docs/networking/dns/dns-records-an-introduction/#dkim

https://www.howtoforge.com/set-up-dkim-domainkeys-identified-mail-working-with-postfix-on-centos-using-opendkim

https://www.centos.org/forums/viewtopic.php?t=63878

https://blog.ceae.info/how-to-install-dkim-with-opendkim-and-postfix-on-a-centos-7/

https://www.linuxtechi.com/configure-domainkeys-with-postfix-on-centos-7/

Hello, I have the same problem with you.
But I have just setup DKIM in vestacp control panel with DKIM information from mailgun.com; But It is not found.
DKIM information like attach file, it can be detail:

Attach File includes Host name and value for DKIM.

Host name:
krs._domainkey.mydomain.com
Enter This Value :
k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCvAvgwNAncGu6TY0UggfcXt7fHgzMxKqWV1LXNAJxqka5zZZ8ioL0mtAT3uo7r/GwbSQS8VVKKzR/C95LLbCholVfMyVyT6BfmcZeFHPfsPxJJBoeERYCMwFoH0jVe9QrfUbMl1TUiDecJuHHSOFDSiixUKKQuDJshH7s9lQtVIwIDARTB

Attach file: http://www.mediafire.com/file/e543be7fwgpbcei/Dkim_02.png

How Do i do to fix this problem?
Thanks!

No one in their right mind is going to download that file.

If you're taking a picture of the vestacp UI, I'd recommend uploading the screenshots to imgur or something. Also, since you're using vestacp, I'd recommend taking a look at this - it seems like a lot of people trying to configure DKIM on vestacp are forgetting that they need to set up the records at their DNS host if they're not using local vestacp nameservers.

You may also have more luck asking this at the vestacp forums - as from a quick Google search, this appears to be a pretty common issue