[Minios-devel] Building with TCP/IP support (daytime) and problems with TCO

[Razvan Cojocaru <razvan.cojocaru93@xxxxxxxxx>]

Hello,

I have tried building mini-os with TCP/IP support using lwip 1.3.2 and initially, the daytime server doesn't reply to TCP requests, even though there is connectivity. In a nutshell, ping works, but netcat on port 13 doesn't.

After some digging, I realized that because of TCP Checksum Offloading, checksums are incorrect and the network stack of the guest system drops any TCP packets received.

In my opinion, there are two ways this issue could be addressed, and I would like to hear an opinion regarding which would be best:

1. Properly document the behavior and mention in the README how to turn off TCO for the guest interface

e.g. # ethtool -K vif<id>.0 tx off

2. Disable TCP checksum validation by default, using lwip's CHECKSUM_CHECK_TCP flag, so that new users (like myself) don't have to worry about these issues.

Thanks,

Razvan

_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel