jas@proteon.com (John A. Shriver) (02/12/91)
In SunOS 4.1.1, udp_cksum is still off. The only progress towards any sort of intelligence on Sun's part is that they finally *document* it, and even cover how to set it by editing one C file when building a kernel. And it finally does affect NFS! (It never did in SunOS 3.X!) We've recently had serious NFS file corruption problems because of the absolute impossibility of enabling NFS/UDP checksums on SunOS 3.5.2, which we still use on a key development machine. (It was due to a bug in a development router corrupting packets.) At least when I upgrade it (someday) to SunOS 4.1.1, I'll get checksums. Presumably, Sun chooses to ignore RFC 1122 (Requirements for Internet Hosts -- Communication Layers). It is dated October 1989, so I seriously doubt that SunOS 4.1.1 had a feature freeze that long ago. (However, we have heard that the path from the TCP/IP group at Sun to SunOS is very long, and fraught with delays, so it may well be that the fix has been in the pipeline for a year. If that is the case, kudos to the TCP/IP group, and would the SunOS group get off their tails!) It would be nice to hope that SVR4 will conform to the host requirements RFC's... To re-quote the section of UDP checksums: 4.1.3.4 UDP Checksums A host MUST implement the facility to generate and validate UDP checksums. An application MAY optionally be able to control whether a UDP checksum will be generated, but it MUST default to checksumming on. If a UDP datagram is received with a checksum that is non- zero and invalid, UDP MUST silently discard the datagram. An application MAY optionally be able to control whether UDP datagrams without checksums should be discarded or passed to the application. I have no idea if Sun would reply to a bid that required RFC 1122 conformance and claim conformance. They don't conform.