With an MD3800F you can connect a host directly to it. In most cases customers will use the sas ports on each controller to connect to the host. Here is the link to the Deployment guide and if you look on page 17 there is a picture showing this configuration. https://topics-cdn.dell.com/pdf/powervault-md3800f_deployment-guide6_en-us.pdf
Please let us know if you have any other questions.