How to pass argument in pxe boot linux image

 PXE server Pls add Linux dd command in this two file and it works.

I have marked as a red color which i have added new entry

1.       /tftpboot/linux-install/pxelinux.cfg/default

default local

timeout 100

prompt 1

display msgs/boot.msg

F1 msgs/boot.msg

F2 msgs/general.msg

F3 msgs/expert.msg

F4 msgs/param.msg

F5 msgs/rescue.msg

F7 msgs/snake.msg

label local

  localboot 1

label 0

  localboot 1

label 1

  kernel /tftpboot/linux-install/vmlinuz

  append initrd=/tftpboot/linux-install/initrd.img ramdisk_size=8638 method=nfs:192.168.1.61:/work/rhel5464 ip=dhcp linux dd

2.   /tftpboot/linux-install/pxelinux.cfg/C0A8013D

default /tftpboot/linux-install

label /tftpboot/linux-install

    kernel /tftpboot/linux-install/vmlinuz

    append initrd=/tftpboot/linux-install/initrd.img  ramdisk_size=8638 method=nfs:192.168.1.61:/work/rhel5464 ip=dhcp linux dd

~

I have added new entry in those file marked as red color.