/etc/rc.conf

ppp_enable="YES"
ppp_mode="ddial"
ppp_profile="yourisp"

/etc/ppp/ppp.conf

default:
  set log Phase command


yourisp:
   set device PPPoE:vr0
   set authname your_username
   set authkey your_password
   set dial
   set login
   nat enable yes
   add default HISADDR