after iso download I check iso but I have:
` gpg --verify swagarch-1901_x86_64.iso.sig swagarch-1901_x86_64.iso
gpg: Signature made Wed Jan 2 13:10:44 2019 CET
gpg: using RSA key 4CD3DCB3EC5D6021
gpg: Good signature from "Mike Kr�ger email@example.com" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner. Primary key fingerprint: 0D43 EFF9 AF9B B4FF AEA4 8A45 4CD3 DCB3 EC5D 6021 `
is this OK ?