I have only two issues with the `muxfs` implementation as it stands:<p>(1) (And the largest problem) is that it requires stable inodes in order to tie the checksums with the actual files. This means (and it's already stated in the article) you can't copy / move / overwrite any of the underlying files without losing the checksums. (Basically it also removes the possibility of accessing one of the mirrors via NFS, FUSE, or anything that doesn't have stable inodes.)<p>(2) (Based on my reading of the article) it doesn't seem to hold a "log" or "sequence" to identify which of the two mirrors are ahead or if they are in sync. In case of a disconnect / reconnect you need to manually tell `muxfs` which is the "newer" one (by using a `sync` before being able to mount it).<p>(I haven't tested it though, I'm running Linux, but I'm quite interested because just last week I thought "why doesn't one implement a FUSE file-system to add checksums and thus prevent bitrot". `muxfs` also adds mirroring.)
Nice concept, and having skimmed it's worth noting:<p>> muxfs needs you!<p>> No filesystem can be considered stable without thorough testing and muxfs is no exception.<p>> Even if I had tested muxfs enough to call it stable it still would not be responsible to expect you to simply take my word for it. It is for this reason that I do not intend to release a version 1.0 until there are sufficient citations that I can make to positive, third-party evaluations of muxfs.<p>> This is where you can help.<p>> I need volunteers to test muxfs, provide feedback, and periodically publish test results.
> a filesystem should automatically check and repair data as it is accessed rather than processing the entire filesystem tree upon every check or repair job.<p>Except this is not sufficient. Flash storage for example is especially susceptible to random bitrot of data over time regardless of whether or not it is ever accessed or even powered on. Ever tried to plug in an old USB stick or SD card only to find out it was totally busted or unreadable? Scanning the entire filesystem and re-checksumming everything is therefore completely necessary.
Other than lack of support for NAS file systems in OpenBSD, is there a reason not to use ZFS (in favor of another file system providing similar features)?
would porting ZFS have been worthwile? I know the CDDL is likely considered toxic to have in the kernel but even in a FUSE way might be worthwhile here, no?