http://931076.nextdoorhk.tech/RedHat/7/images/pxeboot/initrd.img
http://931076.nextdoorhk.tech/RedHat/7/images/pxeboot/TRANS.TBL
http://931076.nextdoorhk.tech/RedHat/7/images/pxeboot/upgrade.img
http://931076.nextdoorhk.tech/RedHat/7/images/pxeboot/vmlinuz