Config DKIM for Zimbra Mail Server with cloudflare DNS

 1. Generate DKIM https://dmarcly.com/tools/dkim-record-generator

    - Domain: mail.yourdomain.com
    - DKIM selector: key1
    - DKIM key length: 2048

2. Add new record at cloudflare

    - Type: TXT Name: key1._domainkey Content: "v=DKIM1; h=sha256; k=rsa; s=email; " "p=MIIBIjANBgkqhkiG9*****47/dk/Hg" "RUtXY55ENGs693W7ad4VDew6Uwr+2DVHN6****b+wIDAQAB"

3. Verify config https://mxtoolbox.com/dkim.aspx

    - Domain Name: yourdomain.com
    - Selector: key1