Jellyfish host values: 

• Type: MX | Name: yourdomain.tld | Destination: mx1-hosting.jellyfish.systems | Priority: 5
• Type: MX | Name: yourdomain.tld | Destination: mx2-hosting.jellyfish.systems | Priority: 10
• Type: MX | Name: yourdomain.tld | Destination: mx3-hosting.jellyfish.systems | Priority: 20

Notes:

• If you are using third-party nameservers, in order to make Jellyfish work, ensure to set up the MX records on the side of your DNS provider. 
• It is not possible to configure Jellyfish for cPanel Webmail related to VPS/Dedicated server.
• Using two mail services on one domain name simultaneously is not possible; however, you can configure them on different subdomains.
• Here's how to avoid spoofing.

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