[ENBD] A comparison of ENBD and DRBD, updated

[Peter T. Breuer]

"A month of sundays ago Richard Sharpe wrote:"
> Once I got it going, I found that I could I could write small files to the
> network device, /dev/nda, but if I tried to write a large file, like 100MB,
> it hung. I hope to give it another try soon.

A possibility (given that you are using nbd 2.2.7) is that
merge_requests=1 is set in the module.  No.  Please don't.
Merge_requests is broken under 2.2 kernels.  It works fine under 2.0 and
2.4 kernels. Volunteers to seek out and backport the 2.4 mechanism
gratefully accepted.

A further possibility is that you are expecting large file support
where there is none. I distinctly recall fixing reported large file
related bugs in the late 2.2.2x versions.

But honestly, these kind of reports are useless unless you pass on
info like kernel version (OK, you did pass nbd version) and
command line used and compilation options and the status output from
/proc/nbdinfo, plus such error messages as you can get.  That's just
basic science.  We have to be able to duplicate your test-rig if you
have a problem.  Otherwise it's just "likely user error".

Peter