Family members and supporters filed into the federal courthouse Thursday morning.
Daniel Boyd, his sons, Dylan and Zakariya, and four other suspects - Anes Subasic, Hysen Sherifi, Mohammad Hassan and Ziyad Yaghi - are all charged with planning terrorism attacks.
Authorities say their operation was being run from a home in Johnston County.
The FBI has said that it seized some two dozen weapons from the Boyd household and that a pit had been dug under their back deck to be used to store the guns.
They also seized more than 27,000 rounds of ammunition, along with $14,000 in cash.
In an interview with agents, Dylan Boyd claimed that the U.S. Army was overseas raping and killing "their" Muslim sisters and repeatedly called the FBI agents questioning him "kuffar" -meaning nonbelievers. He also said the Sept. 11, 2001, terrorist attacks were an "inside job."
The next hearing is set for mid-January. The trial could start next fall.
In the meantime, the suspects are expected to be taken back to a federal prison in Farmville, Virginia, where they are being held under no bond.