Are mirrored systems possible?

[namAehT]

I'm looking into possibly moving a smallish business over to FreeNAS and was wondering if it is possible to mirror a whole system. There are two locations and the idea is to keep both systems datasets and shares synced together so that either system is less than an hour behind the other.

 

[Spearfoot]

I'm looking into possibly moving a smallish business over to FreeNAS and was wondering if it is possible to mirror a whole system. There are two locations and the idea is to keep both systems datasets and shares synced together so that either system is less than an hour behind the other.

Using replication you can keep two systems synchronized.

 

[namAehT]

Using replication you can keep two systems synchronized.

If I'm correct, that will only copy over one way? I would need it to go both ways and be seamless to the end user

 

[Spearfoot]

If I'm correct, that will only copy over one way? I would need it to go both ways and be seamless to the end user

Yes, replication works one way.

I don't understand your goal. :)

 

[namAehT]

I'd like to have two separate servers in two separate locations contain the same set of files. With the ability to add/remove files from either server and have it sync over to the other. I guess I'm trying to mirror the two systems, is this possible?

 

[wblock]

One virtual disk, available at both locations. Maybe a clustered filesystem. Changes made on one system show up on the other. We (iXsystems) sell TrueNAS with a failover feature, but it's not really for that. However, as I understand it, the Minio system might be able to do that. It is slated to be included in one of the upcoming releases of FreeNAS 9.10. That might be initial limited support, with full support to be added later. Worth looking into, though. See the announcement at https://forums.freenas.org/index.php?threads/the-future-of-freenas-9.52207/.

 

[namAehT]

So aside from going with a TrueNAS system and using failover, which to my understanding means locking into specific hardware, I might be better off going with something like GlusterFS?

 

[wblock]

No, the TrueNAS failover feature does not do what you want. Please see the second half of my post.

I have heard of success with GlusterFS from large institutions with dedicated support staff. For anyone else, no.

 

[farmerpling2]

No, the TrueNAS failover feature does not do what you want. Please see the second half of my post.

I have heard of success with GlusterFS from large institutions with dedicated support staff. For anyone else, no.

Having separate sites run using mirrored data on both sites is somewhat complex and not cheap.

Typically used for disaster recovery, you see banks, stock markets use this with sites 50-75 miles apart. Dual separate physical paths dedicated glass is used. Example is OpenVMS clusters with mirrored disks and systems. Not cheap...

 

[namAehT]

Well, this was very informative. Thanks all for answering my questions.

 

[wblock]

I feel like the suggestion I made was missed. Minio might make it possible to set up your own "cloud" storage on your own systems. In other words, a small clustered filesystem. I would suggest investigating that, because FreeNAS 9 will have it, possibly in a limited form to start.

 

[farmerpling2]

I feel like the suggestion I made was missed. Minio might make it possible to set up your own "cloud" storage on your own systems. In other words, a small clustered filesystem. I would suggest investigating that, because FreeNAS 9 will have it, possibly in a limited form to start.

The biggest problem with mirroring between multiple sites is having a big enough pipe to update both sides of the house to be consistent with each other.

If the two systems were only a couple miles apart you could use laser or microwave technology to link the system in real time. You could then have the two systems look like they are local to each other and use some clustering or database software to keep the systems in lock step.

I would suggest that our friend namAehT spend some time to understand his goals and along with some criteria to meet those goals. There are many variables that need to be understood before one can make a suggestion to use X, Y, or Z.

 

[namAehT]

I would suggest that our friend namAehT spend some time to understand his goals and along with some criteria to meet those goals. There are many variables that need to be understood before one can make a suggestion to use X, Y, or Z.

I'm in very early planning stages right now, just trying to get a feel for what is and isn't possible with different platforms. When all the factors are considered (budget, ease of use, amount of data storage,etc) I'll probably end up making a post asking for more advice :)

 

[wblock]

The biggest problem with mirroring between multiple sites is having a big enough pipe to update both sides of the house to be consistent with each other.

Agreed, although it depends on usage. Like with replications, sometimes the initial sync has a lot of data, then there is not that much bandwidth needed to keep up with the differences.

 

[Robert Trevellyan]

How much data do you need to synchronize?