--nftset=/<domain>[/<domain>...]/[(6|4)#[<family>#]<table>#<set>[,[(6|4)#[<family>#]<table>#<set>]...]

Similar to the --ipset option, but accepts one or more nftables sets to add IP addresses into. These sets must already exist. See nft(8) for more details. The family, table and set are passed directly to the nft. If the spec starts with 4# or 6# then only A or AAAA records respectively are added to the set. Since an nftset can hold only IPv4 or IPv6 addresses, this avoids errors being logged for addresses of the wrong type.