# Best operating system for NAS/SAN? (and PERC 6i)



## rocketman331

OpenFiler Free and supports iSCSI targets.

Any Windows OS (except for Server 2008 R2 Datacenter) will require a 3rd part iSCSI app to enable iSCSI.


----------



## W4LNUT5

Well would you prefer a SAN or a NAS? They are slightly different.

For a NAS server, I use FreeNAS as my OS of choice. Really easy to use, and configuration is done mostly by a web interface. BUT, I don't know how well it interacts with PERC cards (I'd imagine it would be fine though)


----------



## sofakng

OpenFiler looks nice but I just realized I'd need to re-initialize my GPT/NTFS array and start over. Does it use a proprietary file system or something?

I'm not sure the difference between NAS and SAN. When I think of SAN I think of iSCSI and when I think of NAS I think of SMB/NFS. I was originally looking at OpenFiler because it appears to support both (so it's both a SAN and a NAS?) but I don't like needed to switch from my NTFS file system.

Also, management of the PERC card is a must... (so I can tell if a drive drops out of the array, etc)


----------



## W4LNUT5

The differences are in how they accomplish the same thing (Network Storage). It sounds like you are looking for NAS.

http://compnetworking.about.com/od/n...san-vs-nas.htm

I know FreeNAS likes you to use UFS. But I'm sure you would be able to use GPT/NTFS with it.

Here's a vid for







YouTube- Step by Step How to Make a FreeNAS Box that I used when setting up mine.

I don't know anything about Openfiler, so I can't help out with that route.

Edit: Since I didn't know anything about Openfiler, here is some info comparing the two

http://forums.whirlpool.net.au/forum...m/1044311.html
http://blog.patyuen.com/lessons/tech...-your-own-nas/


----------



## sofakng

OK - If a SAN typically uses Fibre Channel and other "enterprise" technologies than it sounds like I want a NAS. (they both sound awfully similar though)

FreeNAS looks nice and the Wikipedia page says it supports both NTFS and GPT. I'm not sure on the MegaRAID (eg. PERC management) compatibility though).

Any idea how FreeNAS compares to Windows Server 2008 R2 with the file server role?


----------



## ComGuards

Quote:


Originally Posted by *sofakng* 
OpenFiler looks nice but I just realized I'd need to re-initialize my GPT/NTFS array and start over. Does it use a proprietary file system or something?

I'm not sure the difference between NAS and SAN. When I think of SAN I think of iSCSI and when I think of NAS I think of SMB/NFS. I was originally looking at OpenFiler because it appears to support both (so it's both a SAN and a NAS?) but I don't like needed to switch from my NTFS file system.

Also, management of the PERC card is a must... (so I can tell if a drive drops out of the array, etc)

You don't "give up" NTFS when going with iSCSI.

iSCSI is meant to be an inexpensive alternative (comparatively) to expensive fiber-channel SAN implementations.

In Openfiler, you enable iSCSI support, create an iSCSI drive, connect to the iSCSI device from the server, and then create and format a new NTFS volume as you would any other Windows disk.

You can format an iSCSI target with all of the same file system types as you would any other normal hard-drive.

You should expect to have to do _some_ kind of array / partition modification if you are switching operating systems.

Also, there are other considerations you need to take into account when adding an iSCSI datastore to an ESX(i) system. Mainly power and redundancy. If this is for a development network, then it's not too big of a problem; but if you have any data you plan on storing that's irreplaceable or difficult to replace, you may wish to reconsider.

iSCSI / NFS requires high-availability on the network connections, for one thing. You need to ensure that data communication between the ESX(i) server and the NAS/SAN device can be maintained - this usually means UPS battery backup systems _minimum_ on your network switches AND the NAS / SAN device, otherwise you run the risk of serious virtual machine or virtual disk corruption should a power outage occur, or communication is otherwise dropped between the devices.

There are other considerations in a production environment, but I don't feel it necessary to elaborate here...

I'd probably suggest you invest in better internal storage on your ESX(i) server....


----------



## sofakng

Hmmm, I didn't really think about the high-availability requirement of iSCSI and what would happen if the connection is lost. I suppose it makes sense that there would be file corruption since it's working at such a low-level on the hard drive. (eg. with SMB/NFS I would think the file just wouldn't be saved if a connection problem occured)

Does NFS really have that same problem?


----------



## ComGuards

Quote:


Originally Posted by *sofakng* 
Hmmm, I didn't really think about the high-availability requirement of iSCSI and what would happen if the connection is lost. I suppose it makes sense that there would be file corruption since it's working at such a low-level on the hard drive. (eg. with SMB/NFS I would think the file just wouldn't be saved if a connection problem occured)

Does NFS really have that same problem?

Yes. You run the same risks, according to the last VMWare seminar that I attended.

Unless you have High-Availability (HA) capabilities, you should probably stick with just internal datastore. You don't REALLY need to add an iSCSI SAN datastore unless you're implementing HA or vMotion or some such technology, and you can't implement either one with basic free ESXi - you need a specific paid version of vSphere4.


----------



## Turgin

I have a good friend and co-worker that is heavy into this stuff at home. He has 2 ESX hosts and a shared storage box for his volumes. We talk almost daily about the latest developments with his home network and I can tell you that he recently switched from OpenFiler to OpenSolaris for his storage backend and is very very happy with it. This guy is one of our enterprise storage and VMWare admins so I know he knows his stuff. You may want to check it out as another option.

http://hub.opensolaris.org/bin/view/Main/


----------



## ComGuards

Quote:


Originally Posted by *Turgin* 
I have a good friend and co-worker that is heavy into this stuff at home. He has 2 ESX hosts and a shared storage box for his volumes. We talk almost daily about the latest developments with his home network and I can tell you that he recently switched from OpenFiler to OpenSolaris for his storage backend and is very very happy with it. This guy is one of our enterprise storage and VMWare admins so I know he knows his stuff. You may want to check it out as another option.

http://hub.opensolaris.org/bin/view/Main/

Good suggestion.... 'cept it doesn't address the underlying question of ensuring availability and preventing VM corruption due to connection lost







That's just what I'm drawing attention to - It's not such a big deal if it's a test lab, but if the VMs are going to be storing any kind of irreplaceable data, then that's something that needs to be considered and addressed


----------



## Turgin

Quote:


Originally Posted by *ComGuards* 
Good suggestion.... 'cept it doesn't address the underlying question of ensuring availability and preventing VM corruption due to connection lost







That's just what I'm drawing attention to - It's not such a big deal if it's a test lab, but if the VMs are going to be storing any kind of irreplaceable data, then that's something that needs to be considered and addressed









That's true. I was making a suggestion based on _assuming_ we were talking about a hobbyist or lab scenario. Classic example of the old adage. My friend does have an ESX cluster and uses VMotion. I asked him why he needed/wanted to do this at home and he said...uh cause its cool


----------



## sofakng

Yeah, this server is going to be used in a home environment (as a test lab and home file server, etc). However, I definitely don't want the chance of pictures getting corrupted (or other valuable data), etc.

I've been trying to do my home work and it seems like NFS and iSCSI share the same problem but SMB appears to not have the problem? I'm not sure that makes sense, but does NFS work at a lower-level than SMB so it would be more affected by connection issues?

I would think that if I'm copying a file over to a server and the connection drops then the file just wouldn't get written (instead of it getting written in a corrupted state).

(EDIT: Also, regarding OpenSolaris [and presumably ZFS], I'm currently using my Dell PERC 6i's onboard RAID but am thinking about switching to a software based solution because of the fear of the PERC controller dying and then I'm going to be stuck...)


----------



## Turgin

Quote:


Originally Posted by *sofakng* 
Yeah, this server is going to be used in a home environment (as a test lab and home file server, etc). However, I definitely don't want the chance of pictures getting corrupted (or other valuable data), etc.

I've been trying to do my home work and it seems like NFS and iSCSI share the same problem but SMB appears to not have the problem? I'm not sure that makes sense, but does NFS work at a lower-level than SMB so it would be more affected by connection issues?

I would think that if I'm copying a file over to a server and the connection drops then the file just wouldn't get written (instead of it getting written in a corrupted state).

(EDIT: Also, regarding OpenSolaris [and presumably ZFS], I'm currently using my Dell PERC 6i's onboard RAID but am thinking about switching to a software based solution because of the fear of the PERC controller dying and then I'm going to be stuck...)

It depends on how the partition/volume/LUN is being used. Used as a file share the connection dropping shouldn't affect files other than what's being written. Now, that's assuming it was just the network connection that dropped. A failure of the file server, a power failure and no UPS for example, would be subject to the same corruption potential of any computer that abruptly loses power.

If you're mounting VMWare volumes via NFS or iSCSI then a network disruption would be similar to that guest losing power if it were a physical server.

All that said, I am going to agree with ComGuards and say beef up the internal storage of your ESX host, put it on a UPS if its not, and use that for your volumes. If you need a CIFS/NFS share for another system then run your file server OS of choice in a guest and share it from there.

Now, if you're like my friend and just want the "coolness" (this is overclock.net so I figure you do







) then go for it! Since this is a home network simply performing proper backups of your important data to another media would be sufficient in my opinion.


----------

