On Thursday, April 19, 2012 02:49:41 PM aurfalien wrote: > Trying to mount an FW800 6TB volumes. > The logs say; > cannot find hfs+ superblock Aurf, (it's Friday: and now I'm channelling Michael J Fox in Teen Wolf pronouncing that name... sorry). My first question is: which HFS+ filesystem module are you using, since CentOS 6 by default does not include HFS+ capability? (See: https://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Migration_Planning_Guide/sect-Migration_Guide-Package_Changes-Driver_Changes.html ) There are pretty significant issues with the weakly maintained in-kernel HFS+ filesystem drivers (probably the reason upstream isn't shipping HFS+ enabled by default): see: http://kerneltrap.org/mailarchive/git-commits-head/2009/10/29/11287 Namely, due to a 32-bit data type being used the in-kernel driver can (and will) corrupt any >2TB volume when you try to write above the 2TB 'boundary' even when used in a 64-bit kernel. Now, assuming that you're not already using it, have you tried the trial download of Paragon's commercial HFS+ filesystem? See: http://www.paragon-software.com/home/ntfs-linux-per/ for the free to use Express edition. (I know that says ntfs in the URL; the HFS+ and NTFS filesystems are a bundle). I've done significant data migrations and interchange with HFS+ volumes and various Macs, and the in-kernel HFS+ filesystem is very flakey. I've not had those issues with the Paragon HFS+ filesystem, or for that matter the NTFS filesystem driver that comes in the bundle. The Paragon documentation states that there is no limit on filesystem size imposed by this driver; just limits imposed by the kernel or by the NTFS/HFS+ systems themselves. I've not personally tried a >2TB HFS+ filesystem with this driver, so I'd test it well before using in production. This driver includes read/write access to HFS+ Journaled volumes; the in-kernel driver is read-only for HFS+ Journaled volumes. The Professional version of the driver (available with a free trial period for testing) includes diags, including an fsck and mkfs for both filesystems. Now, to help troubleshoot this a little, you may want to get gdisk from EPEL to see how that thing is partitioned.