TFTP error: 'File not found' - embedded-linux

Question

I am using minicom on Kali Linux native ( Linux 4.6.0-kali1-amd64 x86_64 )
to install embedded linux on a stm32f746g-Disco.
After setting up the tftp protocol, the ethernet connection with the board
, after building the kernel and putting the image in the appropriate folder ( \tftpboot\stm32f7\uImage is the path & name of the image ), I'm starting minicom to comunicate with the board.
The comunication with the board works fine, but the problem is that the board somewhat cannot read the image of the kernel, even if the path is correct:
STM32F746-DISCO> reset
resetting ...
U-Boot 2010.03 (Dec 21 2015 - 04:18:19)
CPU : STM32F7 (Cortex-M7)
Freqs: SYSCLK=200MHz,HCLK=200MHz,PCLK1=50MHz,PCLK2=100MHz
Board: STM32F746 Discovery Rev 1.A, www.emcraft.com
DRAM: 8 MB
In: serial
Out: serial
Err: serial
Net: STM32_MAC
Hit any key to stop autoboot: 0
Auto-negotiation...completed.
STM32_MAC: link UP (100/Full)
Using STM32_MAC device
TFTP from server 172.17.4.1; our IP address is 172.17.4.206
Filename 'stm32f7/uImage'.
Load address: 0xc0007fc0
Loading: *
TFTP error: 'File not found' (1)
Not retrying...
Wrong Image Format for bootm command
ERROR: can't get kernel image! `
The image folder and file is chrooted:
root#DESKTOP-26MQUER:/tftpboot/stm32f7# ls -la
drwxrwxrwx 2 root root 4096 gen 12 16:06 .
drwxrwxrwx 3 root root 4096 gen 10 14:36 ..
-rw-r--r-- 1 root root 0 gen 12 16:06 pippo
-rwxrwxrwx 1 root root 1384352 gen 12 16:02 uImage
the tftp file is this
root#DESKTOP-26MQUER:/tftpboot/stm32f7# cat /etc/xinetd.d/tftp
service tftp
{
protocol = udp
port = 69
socket_type = dgram
wait = yes
user = root
server = /usr/sbin/in.tftpd
server_args = /tftpboot
disable = no
}
Please notice that the xinetd service is active.
I can't understand the problem, guidance will be appreciated.

Answer 1

If have checked all possible point on tftp config, the issue is still there, you can try a standalone tftp server(standalone means not be managed by xinetd):
1, try to install tftpd-hpa
2, config tftpd-hpa
$ sudo vi /etc/default/tftpd-hpa
TFTP_USERNAME="tftp"
TFTP_DIRECTORY="/tftpboot"
TFTP_ADDRESS="0.0.0.0:69"
TFTP_OPTIONS="-l -c -s"
3, start tftp server
$ sudo service tftpd-hpa restart

Answer 2

Even though this is an old thread.In my case it problem was that (CentOS) /usr/lib/systemd/system/tftp.service contained only -s [path to dir] and xinet wasn't using tftp config.So adding switches from xinet tftp config to tftp.service solve my problem.