class hammer match hardware subclass hammer c0 9f 68 98 05 option root

class "hammer" { match hardware; }

subclass "hammer" 1:0:c0:9f:68:98:05 { option root-path "/srv/tftpboot/hammer"; }
subclass "hammer" 1:0:12:f0:71:bf:48;

subnet ... {
    ...
    pool {
        allow members of "hammer";
        range 195.112.124.104 195.112.124.104;
        if exists gpxe.bus-id {
            default-lease-time 5;
            max-lease-time 5;
        }
    }
}