Ethernet link capability between an OSN 2500 N1EFT8A card and an OSN 7500 N1EFS4 card is affected because, from time to time, ping fails when it has a MTU
value set to 1500 bytes. In many cases cold reset or power failure of the board had happened before ping xx.xx.xx.xx �l 1500 command was issued.
OSN 2500 version: 126.96.36.199
N1EFT8A version: 4.13
Due to the chip limitation, if one port of the EFT board has MTU value set to 1535 bytes, and after that a new setting is done on another port, with a value different
from 1535, this new value will be applied to all the ports, including the one set to 1535. In this case, even if in NMS that port X has MTU set to 1535 bytes, actually it
has another value (the last one set on the card).
As a consequence, in case of a board reset or power failure, the MTU value of the last port will be applied to all the other ports after board restart.
Card is broken or has a hardware design limitation.Huawei engineer collected the related logs and run several scripts from Navigator. After further analysis and tests
done by Huawei RND in the lab, it was found that this card has a hardware design of the SD579V1 CMOS chip that forces the last MTU value set on any port to be
applied to all the ports.
For EFT card, on last port, set MTU to the highest value set on any of the other ports. In this way, if a reset occurs, this value will be applied to all the ports, and
ping will work fine.