Dual NAS recommendations

[sb9t]

Hello,

First time FreeNAS user here. Happy to be here but I need advise.

History: (I'll try to keep it short)
I have an openfiler nas that started life as a 500gb nas. Speed wasn't important as all I needed was a central storage location. After a few years I added 9 TB and speed became important. Transfer speeds were reduced and I attributed it to the nas itself since the network was fully gigbit. Recently I rebuilt half my network including all the switches and what do you know, i'm maxing out the gigabit nic on my old NAS. Turns out my gigbit dlink switch was the bottle neck.

Present:
One of my new purchases was a new nas. I originally planned on using the old nas as a giant backup repo for the new nas (i'm aware that i'm a few tb short). After looking at all the features in freenas and discovering that my old Nas is still very fast i'm wondering about my other options. Sounds stupid but i'm basicly looking for configuration advise for two nas devices. I don't really need fail over or clustering, but it couldn't hurt. I'm curious as to what long term freenas users would do?

Old Nas:
Athlon dual core, 3GB Ram, 2x1GB NICs, 9.1 TB (4x2TB, 1x1tb, 1x125gb ssd).
New Nas: Xeon Dual core, 4gb RAM, 1x1GB nic (could easily be 2), 12.2tb (4x3tb, 2x125 ssd)

 

[sb9t]

Sorry, I was kind of rushed when I made my last post.

To elaborate - I was originally planning on using my old nas as an iscsi target for freenas and setup a scheduled task on one of my windows boxes to backup my data. I was going to setup one large striped array on the old nas to use as the repository. This was until I saw the Rsync and replication features in freenas.

Now I’m thinking of switching my old nas over to freenas and setting up replication. But can anyone tell me how well it works? I use DFS so I figured this way I could setup redundancy. However I didn't know if the mismatch in size will pose an immediate problem. Although my new Nas is roughly 4TB big than my old one I’m only using roughly 45% of my old one. I'll have some time before I have space issues on the old nas. If I do this I can also strip all 4 3tb drives in the new nas and all 4 2 tb drives in the old nas yielding more storage on both boxes. I could also stripe just 3 drives on each box and use the 4th as a spare.

I think I have a few options and this is why I’m reaching out to you all for your opinions. Any help or advice would be appreciated.

Thanks.

 

[jgreco]

Replication means ZFS replication; it won't work with a non-ZFS filesystem. It's reasonably cool: you configure one system to push snapshots at another.

rsync doesn't care what you do. It's file-based and should work fine from any moderately-UNIX-like filesystem to any other.

 

[sb9t]

Thanks for the reply jgreco.

With replication pushing snapshots from the new nas to the old nas, would I be able to use the data directly from the old nas? If the new nas was unavailable can I just browse the data on the old nas just the same as the new nas with out jumping through hoops?

What's the consensus of using a striped raid without parity? In a production environment I wouldn't even consider it but for my home I'm a little more flexable. I'm just not sure about how dangerous it really is. With 2 nas devices I feel more comfortable about it but I'm a very indecisive person so I'm just looking for what others would do to help me make my decision. It would be nice to not have to recopy the entire nas every time a drive fails in either direction. It would be nice to just swap a drive and let the raid figure itself out. At the same time this shouldn't be a common procedure since the drives in my old nas are only a year old and the drives in my new nas are brand new. Although I don't really need the space now 4x3tb stripped is way more available space than 4x3tb in a raid5... or should I say raidz. Plus I can't help but think i'll be that guy who loses a drive in both nas devices at the same time but no one can be that unlucky.

What are your thoughts?

 

[louisk]

Right now, there is no way to have hot fail-over with FreeNAS (outside of using other gadgets). That means you would have to reconfigure the IP of one of your NAS units to replace the failed one, OR you would have to reconfigure your clients to point to the other NAS.

I would not use striped on anything I wasn't willing to lose. If your data exists on 2 different NASs, you could have one of them striped and not worry about it. I would not be willing to put my data only on a stripe, although I would be willing to use a stripe if I had either duplicate data elsewhere, or a tape backup.

I'm currently running my data on a pool of mirrors (effectively raid10). If you have a spindle failure, you will have to replace the hardware, and then go into FreeNAS gui and tell it to use the new drive. Its not like hardware RAID that detects a new drive and automagically starts rebuilding. That said, I've been running FreeNAS on a couple of different hardware configurations over a number of years and I've never had any significant problems replacing drives with ZFS/FreeNAS.

I can't tell you what the value of your data is, only you can know that. I value my data, and I use mirrors. Some might think that is extreme. OTOH, I know I can lose up to 4 of my 8 spindles and not have any data loss. I also keep an extra 4 spindles as spares for when I do have a disk failure.

 

[sb9t]

I'm planning on using DFS for the redundancy. My data isn't read only but it's static enough to not pose a problem. Plus the chances of two people modifying the same file at the same time is slim to none.

I think I'm talking myself out of stripping the data. Let's be realistic, after parity and fs overhead my old nas has 6.1 tb of usable space with 1.6 Tb used. My new Nas has 8.6TB available after parity and fs overhead. At my current rate of growth it would be about 2 years before I need to add space and I have space for 2 more drives in my current chassis. Even with 2 nas devices, I don't think with my current rate of growth it's worth the risk of not having a parity disk. I think I just like the idea of having roughly 10Tb of usable space.

Now I just need to figure out how I want to backup the data. I can either use dfs and setup replication or Rsyn. This will give me a failover and load balanced solution. Or I can setup my old nas as a iscsi target to either my new nas or my backup server. This doesn't give me any failover or load balancing but my data is backed up. Hell, while I'm at it I could always setup both nas devices as Iscsi targets and use 2 windows servers as initiators in a cluster. I have about 4 licenses left for server 2008 enterprise.

It sucks being indecisive! It's harder for me to figure out how I want things configured than it is to actually configure it.

 

[louisk]

What are the requirements?

 

[sb9t]

What are the requirements?

The must have list goes as followed:
14 day retention of server images.
5 day retention of workstation images.
5 day retention of misc shared data.
1 mirror of mutli-media data. - Right now I have the space to accommodate days worth of media data but eventually that wont be possible due to the old Nas being smaller than the new one. I just don't want to have to revisit the configuration of this system.

The Wish list:
fail over.
load balancing.


I think I might just setup my old Nas as a iscsi target to either my new nas or my backup server. DFS wont work for linux and pc's not joined to my domain so my media system wont benefit at all. It's also not true load balancing. Clustering would give me actual fail over and load balancing but my windows servers would have to be vm's and I don't know how that would affect performance. I might have to add a couple more nics to the vm host.

 

[louisk]

Seems to me, if you're thinking about replication, you have 2 options.
1) use the old nas as the primary, replicate to the new nas.
2) get 2 new nas, and replicate from one to the other.
I don't know how much data you generate over a period of time, but you should probably work that into a document detailing your growth and get somebody to sign off on approving additional storage when the time comes, or you will get stuck not being able to provide your storage service to your users.

If you're going to replicate data, I would suggest that you start with relatively recent hardware, as opposed to one new and one old.

Short of putting a cheap load balancer (or building one if you feel like it), I don't know of a good solution for this using FreeNAS. If this is going to be a work kind of solution, you might investigate TrueNAS, you pay for it, but you also get commercial support and some additional features like fail-over, and dedupe.