I'm thinking about getting a Drobo S to add some storage on a Windows Server 2008 R2 box. The Drobo offers thin provisioning.
While I will only have 4.5TB of space initially, I'd like to use thin provisioning to create a 16TB LUN.
If the OS sees this as 16TB even though there is only 4.5TB available, what happens when I run out of physical space? Is there some way for the Drobo to report to the OS that it is full, despite the free cluster count of the NTFS partition saying otherwise?
I've been pondering for a long time about how I can set up a server which operates much like the Drobo storage thing. The reasons I don't actually want a drobo is because I've heard scare stories, plus I'd like to do this on the cheap.
So ideally I'm looking for something like lvm so I can create a logical volume that spans many hard disks of varying sizes... obviously that only offers redundancy if I put the LV on a raid array (as far as I know..) I have however been reading about technologies such as Microsoft's drive extender which duplicates files at the filesystem level and makes sure that the mirrored files are on a different phyiscal disk.. does anyone know or recommend a filesystem or method like this as it'll hopefully make much better use of the space available than raid ever could.
Performance isn't an issue, I'd just really like to make the most of the hard disks I have lying around whilst having a bit of redundancy incase a disk dies. I understand full well that this is no replacement for a backup, but I'll only be storing files of medium importance and using the nas itself as a backup of my main pc and other systems.
Thanks in advance! I'm hoping zfs or btrfs or something can do something clever for me :)
I have a 2TB ext4 file system (Ubuntu running Linux kernel 2.6.31-22-server x86_64). This file system is the second drive on a Drobo box plugged in via USB. We've not had problems on the first drive (Drobo limits drive size to 2TB due to some OS limitations, so if you have more space than that it appears as two separate drives).
I am sharing this files with Samba (smbd 3.4.0) with a mix of Windows and Linux workstations.
Recently we've been experiencing some data corruption in multiple files. In many cases I have an un-corrupt original file stored on one of the workstations. These are binary files of various formats, (e.g. SQLite, but others as well).
I used "split" to split a corrupt and uncorrupt file into 4096 byte chunks (this is the block size of the ext4 file system). I then ran md5sum on pairs of chunks and discovered that the chunks matched in many cases and in every case where they did not match, the corrupt chunk was a solid chunk of zeroes (620f0b67a91f7f74151bc5be745b7110 for what it's worth).
I'm trying to track down a culprit but am a bit at a loss. I don't believe Samba is at fault since I'm using it without issue on the first drive exported by the Drobo.
What can I do to narrow this down and find out what's going on?
Current situation:
All four servers are running standalone. The two ESX servers are beginning to run out of hard drive space but still doing very well on the processing and memory fronts. We're not running any external iSCSI or SAN storage for the servers at all.
The ESX servers are also running Ultra320 SCSI drives which are beginning to get very pricey at low storage rates ($550 for 300GB!), so I want to shy away from just throwing more 'small' drives at the ESX servers knowing the hard drives will become rarer with time in the event of drive failure.
What is probably the best solution? Right now I'm looking at the DroboPros which will allow for more growth over a longer period of time, which looks nice for budgets, or at a Dell Poweredge 2950 with 2TB of storage (using 3 bays out of 6 in RAID 5) but still room to grow since it runs SATA for around $3400.
I'm also looking at trying to get vCenter and vMotion, but would there be any advantages to the above two solutions over each other? By switching to external storage I'm hoping to not have to replace these servers until they are maxed out on RAM usage or the CPU load is finally too great.
Update
I will be going with either the PowerEdge bumped up to support SAS drives or a PowerVault with SAS, with the intention to end up running our VMWare from the external storage. The DroboPro is nice but not a long term solution. Here's hoping I get the PowerVault!
Thanks for the great answers everyone!
I'm looking at picking up a fully loaded drobo pro this year (last quater). Has anyone actually found any benchmarks on it yet? I've seen many people saying the speed of the current drobo mk2 is less than steller. I'd be probably looking to use it via the iSCSI interface though which I've anecdotally seen at +50% over fw800 speed.
Has anyone actual evidence of the speeds yet?