ServerBear Specs on Scale HC3
-
The blocks are mirrored. No matter what you write to one node, it is replicated to at least one additional node. But no node is a "pair".
-
@scottalanmiller said:
@Dashrender said:
@scottalanmiller said:
hich it is built. XS with XO would give you the same basic "single pane of glass" interface stuff, but you aren't getting a Scale for
How do you have three nodes and only loose 50% storage, yet loose nothing when a node fails?
RAIN mirroring
In RAID terms, think of network RAID 1+.Is RAIN mirroring always 50% available? I know I know.. mirroring kinda implies that, but I have to ask the question anyway.
Also, what manages this? I assume this management is also mirrored out over the nodes?
-
@Dashrender said:
Is RAIN mirroring always 50% available? I know I know.. mirroring kinda implies that, but I have to ask the question anyway.
Yes, mirroring is always 50%. RAIN is not always mirroring.
-
@Dashrender said:
Also, what manages this? I assume this management is also mirrored out over the nodes?
Each node has a completely independent management system. You can log into any of the nodes to manage the cluster. It's a multi-master system. So fully HA there, not even a blip if a node goes down (unless you are looking at the interface for that specific node.)
-
@scottalanmiller said:
The RAIN storage here mirrors at the block level across the cluster providing a very high durability storage layer. And very importantly that's a native storage layer, in the kernel. There is no VSA here, this is a more advanced and more powerful approach. The storage layer runs right in the hypervisor kernel.
A couple of my colleagues told me they lost TWO nodes in their 4 node scale cluster... and everything kept right on trucking... and these units are the 3-year old models.
-
@dafyre said:
@scottalanmiller said:
The RAIN storage here mirrors at the block level across the cluster providing a very high durability storage layer. And very importantly that's a native storage layer, in the kernel. There is no VSA here, this is a more advanced and more powerful approach. The storage layer runs right in the hypervisor kernel.
A couple of my colleagues told me they lost TWO nodes in their 4 node scale cluster... and everything kept right on trucking... and these units are the 3-year old models.
That can easily work as long as you don't use your capacity all the way up. If you lose them one at a time and it has time to rebalance you would be all set in any way. If you lose two at exactly the same time, it's a bit more of luck
-
@mlnews said:
@dafyre said:
@scottalanmiller said:
The RAIN storage here mirrors at the block level across the cluster providing a very high durability storage layer. And very importantly that's a native storage layer, in the kernel. There is no VSA here, this is a more advanced and more powerful approach. The storage layer runs right in the hypervisor kernel.
A couple of my colleagues told me they lost TWO nodes in their 4 node scale cluster... and everything kept right on trucking... and these units are the 3-year old models.
That can easily work as long as you don't use your capacity all the way up. If you lose them one at a time and it has time to rebalance you would be all set in any way. If you lose two at exactly the same time, it's a bit more of luck
It was a whole lotta luck for them, lol. They're not running at full capacity, so they were safe.
-
@dafyre said:
@mlnews said:
@dafyre said:
@scottalanmiller said:
The RAIN storage here mirrors at the block level across the cluster providing a very high durability storage layer. And very importantly that's a native storage layer, in the kernel. There is no VSA here, this is a more advanced and more powerful approach. The storage layer runs right in the hypervisor kernel.
A couple of my colleagues told me they lost TWO nodes in their 4 node scale cluster... and everything kept right on trucking... and these units are the 3-year old models.
That can easily work as long as you don't use your capacity all the way up. If you lose them one at a time and it has time to rebalance you would be all set in any way. If you lose two at exactly the same time, it's a bit more of luck
It was a whole lotta luck for them, lol. They're not running at full capacity, so they were safe.
One of the nice things about scale out is that it also often means "scale back". So if you are not over using the system, it can rebalance as you fail back to a smaller system.
You can also replicate entire clusters for even more reliability.
-
The more I read about Scale and peoples views the more I want it!!!!!!
Now to just get the board and management to think we need to refresh our hardware lol
-
I guess I just don't get it. This is basically just Dell Servers running via a VSAN connected over 10GB networking. I guess I don't see what's so special about it.
-
@aaronstuder said:
I guess I just don't get it. This is basically just Dell Servers running via a VSAN connected over 10GB networking. I guess I don't see what's so special about it.
It's not the hardware that makes it special. It's the software they run behind it all. The storage provides similar features to VSAN, except you have the ability to simply add another node to expand storage. I'm not sure how that works with VSAN... but with Scale, all you have to buy is another node... no extra software licenses or anything like that.
-
@aaronstuder said:
I guess I just don't get it. This is basically just Dell Servers running via a VSAN connected over 10GB networking. I guess I don't see what's so special about it.
Well that alone would be pretty special as it is far cheaper than running VSAN. VSAN and the full VMware stack is a direct competitor. Scale is older than VSAN. VSAN is SAN based, though, Scale is not. This is fully direct IO, no extra SAN layer. The kernel talks directly to the storage, no translation.
-
@dafyre said:
It's not the hardware that makes it special. It's the software they run behind it all. The storage provides similar features to VSAN, except you have the ability to simply add another node to expand storage. I'm not sure how that works with VSAN... but with Scale, all you have to buy is another node... no extra software licenses or anything like that.
And it "just expands". Really easily to grow. And tiering is right around the corner.
-
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this? Of course you wouldn't have their pretty interface, but could you build this yourself, like a person building XO themself?
-
@Dashrender said:
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this?
Sure, you'd have to write your own storage layer, though. So it's not trivial in any way.
-
@scottalanmiller said:
@Dashrender said:
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this?
Sure, you'd have to write your own storage layer, though. So it's not trivial in any way.
OH.. that's where I was confused I guess... I thought the storage layer was part of KVM (that's the hypervisor they use, right?)
-
@Dashrender said:
@scottalanmiller said:
@Dashrender said:
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this?
Sure, you'd have to write your own storage layer, though. So it's not trivial in any way.
OH.. that's where I was confused I guess... I thought the storage layer was part of KVM (that's the hypervisor they use, right?)
Not part of KVM itself. The Scale HC3 is unique, there is no software version available on the market.
-
@scottalanmiller said:
@Dashrender said:
@scottalanmiller said:
@Dashrender said:
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this?
Sure, you'd have to write your own storage layer, though. So it's not trivial in any way.
OH.. that's where I was confused I guess... I thought the storage layer was part of KVM (that's the hypervisor they use, right?)
Not part of KVM itself. The Scale HC3 is unique, there is no software version available on the market.
So they wrote the storage layer? Cool - good to know/understand that.
-
@Dashrender said:
@scottalanmiller said:
@Dashrender said:
@scottalanmiller said:
@Dashrender said:
Scott, you mentioned that this is all at the kernel level - could you roll your own version of this?
Sure, you'd have to write your own storage layer, though. So it's not trivial in any way.
OH.. that's where I was confused I guess... I thought the storage layer was part of KVM (that's the hypervisor they use, right?)
Not part of KVM itself. The Scale HC3 is unique, there is no software version available on the market.
So they wrote the storage layer? Cool - good to know/understand that.
Yes, Scale is primarily a storage vendor. Before they made their Hyperconverged product, they made scale out storage only. That was before KVM was mature enough to make the HC3 product. They no longer sell the storage layer, it is now developed purely and designed solely around the needs of the HC3 product so is completely unique to that. It's the storage layer and the storage integration (and support) that are their selling points. That's what makes them special and unique. KVM and the hardware on its own you could do yourself and you could easily make due with a different interface.
