Yocto Setup TFTP/NFS
Running Yocto rootfs on Variscite board using TFTP & NFS
On the Host
Prepare the rootfs folder:
$ cd ~/var-fslc-yocto $ sudo mkdir rootfs $ cd rootfs $ sudo tar xvf ../build_x11/tmp/deploy/images/imx6ul-var-dart/fsl-image-gui-imx6ul-var-dart.tar.gz
Make sure the NFS server is installed:
$ sudo apt-get install nfs-kernel-server
Edit /etc/exports. E.g.
$ sudo nano /etc/exports
...and add the following line to it (replace <uname> with the actual username):
/home/<uname>/var-fslc-yocto/rootfs *(rw,sync,no_root_squash,no_all_squash,no_subtree_check)
Restart the NFS server:
$ sudo /etc/init.d/nfs-kernel-server restart
Make sure the TFTP server is installed:
# Ubuntu 24.04 and newer $ sudo apt-get install xinetd tftpd-hpa tftp-hpa # Ubuntu 22.04 and older $ sudo apt-get install xinetd tftpd tftp
Configure tftpd-hpa for Ubuntu 24.04 and newer:
$ sudo nano /etc/default/tftpd-hpa TFTP_USERNAME="tftp" TFTP_DIRECTORY="/tftpboot" TFTP_ADDRESS=":69" TFTP_OPTIONS="--secure"
Configure tftpd for Ubuntu 22.04 and older:
$ ls /usr/sbin/in.tftpd $ sudo nano /etc/xinetd.d/tftp service tftp { protocol = udp port = 69 socket_type = dgram wait = yes user = nobody server = /usr/sbin/in.tftpd server_args = /tftpboot disable = no }
and run:
$ sudo mkdir /tftpboot $ sudo chmod -R 777 /tftpboot $ sudo systemctl restart xinetd $ sudo systemctl restart tftpd-hpa
$ cd ~/var-fslc-yocto/build_x11/ $ sudo cp tmp/deploy/images/imx6ul-var-dart/zImage /tftpboot $ for f in tmp/deploy/images/imx6ul-var-dart/*.dtb; do if [[ -L $f ]] && [[ $f != *imx6ul-var-dart.dtb ]]; then sudo cp $f /tftpboot; fi done $ sudo rename 's/zImage-//' /tftpboot/zImage-*.dtb
Make adjustments to the rootfs:
When using NetworkManager on the target, configure NetworkManager not to manage the interface used for the NFS boot by adding the following to /home/<uname>/var-fslc-yocto/rootfs/etc/NetworkManager/NetworkManager.conf:
[keyfile] unmanaged-devices=interface-name:eth0
Enable DNS:
$ sudo ln -fs /proc/net/pnp /home/<uname>/var-fslc-yocto/rootfs/etc/resolv.conf
On the Target
Make sure you have a serial connection to the target.
Boot the board and hit any key to stop the autoboot and get to the U-Boot command line. Run the following in the U-Boot command line:
=> setenv serverip <HOST_IP_ADDRESS> (replace <HOST_IP_ADDRESS> with the actual IP address of your host - run 'ifconfig' on the host to get it) => setenv nfsroot /home/<uname>/var-fslc-yocto/rootfs (replace <uname> with the actual username) => setenv bootcmd run netboot => saveenv
You are all set. Connect the target board to the same network as the host using an Ethernet cable, power cycle it and it should boot over NFS.