NFS: server wrote zero bytes in Fedora Linux
Posted: 15. Jul 2009, 20:28
I had a server running Fedora 10 host, VirtualBox 2.2.4, Fedora 10 client. Networking was bridged. The client NFS mounts a filesystem on the host and writes data there. The files I'm writing are usually a few GB. The filesystem is ext4. I think it's using NFS3 because I didn't ask for NFS4 and it would have used the newest version it could.
I then updated the server to Fedora 11 and VirtualBox 3.0.2. At this point I would find that my application would run for a while and then eventually error out with an I/O Error. If I checked the syslog on the client I'd see a message: kernel: NFS: Server wrote zero bytes, expected 4096. The amount of data copied varied. It might be a few hundred GB up to a couple GB.
Then I backed the VirtualBox version down to 2.2.4, but the same problem happened.
That implies that the problem is only happening in Fedora 11 hosts. I have written big files from Fedora 6, Fedora 8, and Fedora 11. I don't have another non-virtual Fedora 10, but it appears that Fedora 11 handles the big file copies on non-virtual hosts just fine.
Anything else I can try?
I then updated the server to Fedora 11 and VirtualBox 3.0.2. At this point I would find that my application would run for a while and then eventually error out with an I/O Error. If I checked the syslog on the client I'd see a message: kernel: NFS: Server wrote zero bytes, expected 4096. The amount of data copied varied. It might be a few hundred GB up to a couple GB.
Then I backed the VirtualBox version down to 2.2.4, but the same problem happened.
That implies that the problem is only happening in Fedora 11 hosts. I have written big files from Fedora 6, Fedora 8, and Fedora 11. I don't have another non-virtual Fedora 10, but it appears that Fedora 11 handles the big file copies on non-virtual hosts just fine.
Anything else I can try?