On Tue, 11 Feb 2014 10:30:13 +0100 Gionatan Danti <g.danti@xxxxxxxxxx> wrote: > Hi all, > I have a strange problem trying to re-share, via Samba, a CIFS mount. > > Let first explain my network topology: > > Win2008R2 w/SMB share -> low speed link -> Linux Box -> WIN7 clients > > In short, a Win2008 R2 share is being accessed by some W7 clients over a > slow (~8 Mb/s downstream, ~1 Mb/s upstream) ADSL link. To speed up read > operation on the branch office, I thought to use a Linux Box with > cachefilesd and a CONFIG_CIFS_FSCACHE enabled kernel. The Linux box will > mount the Win2008R2 share and, thanks to cachefilesd, it will maintain > an "hot cache" of the read data. This CIFS mount is then shared, via > Samba, to the other client Win7 PCs. > > However, the problem is that when re-sharing the CIFS mount, the Win7 > clients often see the many directories inside the mount as a regular > files, and not directories! In other words, if I have a directory "test" > inside the mount, the client PC will see a _file_ called "test". When > double-clicking on that "file", the Win7 client even ask to select the > application to open it. > > The strange this is that this problem happen with some Linux kernel > version, but not with others. These are my results: > > 1) Stock CentOS 6.5 x86-64 system (kernel 2.6.32-431.1.2.0.1, cifs-utils > 4.8.1-19, samba 3.6.9-167): no problem here, but this kernel does not > have CONFIG_CIFS_FSCACHE, so I can not use it for speeding up read access; > > 2) CentOS 6.5 x86-64 with ElRepo updates (kernel 3.10.28-1): here > CONFIG_CIFS_FSCACHE is enabled, but I have the problem described above; > > 3) Debian 7 amd64 with latest updates (kernel 3.2.54-2, cifs-utils > 2:5.5-1): CONFIG_CIFS_FSCACHE is enabled, problem happens; > > 4) Fedora 20 x86-64 (kernel 3.12.8-300, cifs-utils 6.3-1, samba > 4.1.3-2): CONFIG_CIFS_FSCACHE is enabled and problem does _not_ happen, > however this is a client distro and I am not so comfortable to put it > into production. > > Anyone has any explanation of what is happening here? > Regards. > Most likely, the problem is that the cifs mount is returning an st_nlink value of 0 for directories, and that confuses samba into thinking that directories are files (I forget their rationale for this). More recent kernels have patches that make the client fake up st_nlink values when the server sends 0 for a NumberOfLinks value. -- Jeff Layton <jlayton@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
