How can I solve the problem of "SPM, DKIM did not pass" to send email through postfix with port 25 from local pc?

Error:

to=<abcd@gmail.com>, relay=gmail-smtp-in.l.google.com[74.125.130.26]:25, delay=2.5, delays=0.02/0.01/1.6/0.82, dsn=5.7.26, status=bounced 
(host gmail-smtp-in.l.google.com[74.125.130.26] said: 550-5.7.26 This mail has been blocked because the sender is unauthenticated. 550-5.7.26 Gmail 
requires all senders to authenticate with either SPF or DKIM. 550-5.7.26  550-5.7.26  Authentication results: 550-5.7.26  DKIM = did not pass 550-5.7.26  
SPF [mydomain.com] with ip: [a.b.c.d] = did not pass 550-5.7.26  550-5.7.26  For instructions on setting up authentication, go to 550 5.7.26  
https://support.google.com/mail/answer/81126#authentication j23-20020a632317000000b005f0a5131be5si9917986pgj.293 - gsmtp (in reply to end of DATA command))

Here, a.b.c.d is the public ip address. It is dynamic ip address. I think, it is the router's public ip address. Local pc has ip address like 192.168.1.103.

I am trying to send email to gmail through postfix with port 25 from local pc or localhost. I have installed postfix, opendkim and configured these. /etc/hostname has "mydomain.com". So the sender is user1@mydomain.com.

I have followed this website: https://netcorecloud.com/tutorials/c...stfix-ubuntu//

How can I solve the problem of "SPM, DKIM did not pass" to send email through postfix with port 25 from local pc? I have done the steps following that website to configure DKIM.

1) Link you give to the tutorial doesn't work.
2) Have you correctly configured SPF to reflect your public IP address? - You can test that here: https://www.appmaildev.com/en/spf
3) Have you published the relevant selector for your domain in DNS? - You can also test DKIM signing here: https://www.appmaildev.com/en/dkim

1) I have edited the link. It should work now.
2) Checked there, SPF permerror:
What is the way to configure SPF to reflect public IP?
3) Got error: DKIM permerror. I have put DKIM TXT record in mydomain.com as default._domainkey

Originally Posted by cola 2) Checked there, SPF permerror: What is the way to configure SPF to reflect public IP?

If you don't know how to configure an SPF entry then try: https://mxtoolbox.com/SPFRecordGenerator.aspx

Please post your thread in only one forum. Posting a single thread in the most relevant forum will make it easier for members to help you and will keep the discussion in one place. This thread is being closed because it is a duplicate.

https://www.linuxquestions.org/quest...pc-4175736093/