@arrowgtp The “nslookup” command is short for “name server lookup.” It’s roughly the equivalent of
dig google._domainkey.alma.vacations -t TXT.
The “-type=txt” switch specifies what specific DNS records you want to query.
Because this record is set up as a subdomain by Google, you have to query the subdomain, thus
The next two lines – the Server and the Address – simply show the source of the information to be presented.
The “answer” is the key bit. This shows the contents of the TXT DNS entry for this subdomain. It’s similar to the results from the
dig command, which are:
google._domainkey.alma.vacations. 3599 IN TXT "v=DKIM1; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAho0dO5/TQdyzkSiQaL6oUMki9e1ZzfxS80dRJwyrm4ZTjaP3HL0IqNVxMYMPSZ7on2YCAIqVux9EStMMeY6sXx/UHOGlxppoHje+UEygREjcK60Bdh9O6TIX+HcGhmTvg0443ExHMSHDEHqSw0h9TsSA6A3pe+bNDiFSXi4409eZBPk1YAHfZAu4TL8dhjVTi" "f1Peh5LoX+Age4DXgJnVwYNUkd+TSxhV6hpWc6RuHSB8MC9TwrgshcaGELrzP6XV+IfOs6nsUf/jj9FTh5HLepbns6eutRXKZMAePZMhXw0F9+oVEAaepp0A8VLSRY1tNmvdg4Sny9u/TudXFgSxQIDAQAB"
If this string deviates in even the smallest way from what Google is expecting, they will not verify / validate your control of this domain name.
This should – actually, must – match the text string that Google gave you to complete the validation process.