I've setup a whole new VPS according this howto. I use an external DNS. Everything works really nice, but there is an issue with my DNS TXT record at the DNS provider. The output of amavisd-new testkeys domain.tld gives the output: invalid (public key: not available). When I send an e-mail to a GMail account for example, I see the error code dkim=temperror (no key for signature) in the source of the e-mail. The format of the suggested DKIM DNS record, generated in ISPConfig for domain.tld does not seem to be ok as an DNS TXT record at my external DNS-provider. I tried the record with and without " ", but nothing seems to work. I still got invalid (public key: not available). What might be the solution for this? *UPDATE* Solved. ISPConfig3.1 with DKIM works out of the box. I had to change the host in DKIM TXT record at my external DNS provider from default._domainkey.domaint.tld into default._domainkey.
Questions About DKIM Setup I have setup a new VPS installation according to https://www.howtoforge.com/tutorial...-9-stretch-apache-bind-dovecot-ispconfig-3-1/ Everything is working fine. I am using Name servers of my VPS services data centre I have also setup DNS in Ispconfig control panel & steps followed are as under; 1. Add new DNS zone with Wizard & filled the relevant information Template: Default Server: server.mydomain.com Client : (mydomain,C1) Domain: mydomain.com IP Address: xxx.xx.xx.xxx NS1 : ns1.vpsprovider.net NS2: ns2.vpsprovider.net Email: [email protected] CheckBox : DKIM ============ I checked this Box SignZone Create DNS Record It created successfully with following; On clicking created Zone following values are being shown; Server: server.mydomain.com Client: (mydomain,C1) Zone: mydomain.com. NS : ns1.vpsprovider.net. Email: webmaster.mydomain.com. Refresh: 7200 Retry: 540 Expire:604800 Minimum: 3600 TTL:3600 Allow Zone transfers to these Ip === No Value ( Blank) Allow Notify: No Value ( Blank) Update ACL: No Value ( Blank) Active: Box is checked Sign zone (DNSSEC) Box is unchecked DNSSEC : Blank Box On Clicking Records, following values are being shown Active Type Name Data Priority TTL Yes A mydomain.com. IP address 0 3600 Yes A mail IP address 0 3600 Yes A www IP address 0 3600 Yes MX mydomain.com. mail.mydomian.com 0 3600 Yes NS mydomain.com. ns2.vpsprovider.net. 0 3600 Yes NS mydomain.com. ns1.vpsprovider.net. 0 3600 Yes TXT mydomain.com. v=spf1 mx a ^all 0 3600 If I click on DNS DKIM (Green Button); Then I see following as BLANK Public Key : Box Blank & frozen DKIM-Selector: Blank & frozen TTL : 3600 Active: Box Checked Then I went back to EMAIL > Domain & clicked on Tab DomainKeys Identified Mail(DKIM) & Shows following Values Enable DKIM – I checked this Box DKIM-Selector: default DKIM-Private Key: Blank Box Then I clicked on Generate DKIM-Private-Key On clicking this both the boxes DKIM-Private key & DNS-Record were filled with values Then I saved it! After waiting for couple of minutes, I could see If I click on DNS DKIM (Green Button); Public Key : Filled with Values DKIM-Selector: Fiiled with values My Question, is the right way to create DKIM Key Let me know if I missed anything on DKIM Thanks & regards,