NFS kernel options

This line

root=/dev/nfs rw nfsroot=192.168.0.11:/srv/tftpboot/buildroot,tcp,vers=4 ip=dhcp rootfstype=ext4

• root=/dev/nfs - specify location of root filesystem. For local systems it usually looks like root=/dev/sda1 or root=UUID=80efa619-1b3a-4a17-92a3-e60334584d9f

• rw - root filesystem will mounted in read-write mode

• nfsroot=192.168.0.11:/srv/tftpboot/buildroot,tcp,vers=4 - using NFS client it will access remote location and specify /dev/nfs

• ip=dhcp - this will configure network interface and 192.168.0.11will become reachable

• rootfstype=ext4 - remote NFS filesystem mounted on local machine as ext4

Still a question

tcp,vers=4

or

tcp,v4

PXELINUX syntax

LABEL buildroot
    MENU vesamenu.c32
    MENU LABEL Custom Buildroot build
    KERNEL /buildroot/boot/bzImage
    APPEND root=/dev/nfs rw nfsroot=192.168.0.11:/srv/tftpboot/buildroot,tcp,vers=4 ip=dhcp rootfstype=ext4 --

GRUB syntax

menuentry "Custom Buildroot build" {
        set gfxpayload=keep
        linux   /buildroot/boot/bzImage root=/dev/nfs ip=dhcp nfsroot=192.168.0.11:/srv/tftpboot/pxe_system,tcp,v3 rootfstype=ext4 rw --
        initrd  /buildroot/boot/initrd.img
}