Tool/software: Linux
hello,
I input the instruction at the terminal of AM5728： ethtool eth0，and it prints:Speed: 1000Mb/s.
but when I input:ifconfig eth0 mtu 1000, it can not work.
So I modified the kernel parameters ( 1500 changed to 9000) and recompile the AM5728 kernel.The modifications are as follows：
linux-rt-4.4.41+gitAUTOINC+968d071ce9-g968d071ce9/include/uapi/linux/if_ether.h
#define ETH_DATA_LEN 1500 / Max. octets in payload /
linux-rt-4.4.41+gitAUTOINC+968d071ce9-g968d071ce9/include/linux/if_vlan.h
#define VLAN_ETH_DATA_LEN 1500 / Max. octets in payload /
then execute instructions ifconfig,and print: UP BROADCAST RUNNING MULTICAST MTU:9000 Metric:1
When I used ping to test the packet size, I found that the network transmission data was still unable to transmit over 1500byte！！！
root@am57xx-evm:/# ping -s 2000 www.baidu.com
PING www.baidu.com (111.13.100.92): 2000 data bytes
^C
--- www.baidu.com ping statistics ---
8 packets transmitted, 0 packets received, 100% packet loss
root@am57xx-evm:/# ping -s 1400 www.baidu.com
PING www.baidu.com (111.13.100.91): 1400 data bytes
1408 bytes from 111.13.100.91: seq=0 ttl=50 time=37.617 ms
1408 bytes from 111.13.100.91: seq=1 ttl=50 time=36.952 ms
1408 bytes from 111.13.100.91: seq=2 ttl=50 time=36.800 ms
^C
--- www.baidu.com ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 36.800/37.123/37.617 ms
Although you can make mtu's value of 9000 by modifying the kernel, you can't actually transfer jumbo frames！！！
Please help me analyze how to solve this problem.Looking forward to your professional reply,thanks.
