XenServer 7: best practice: noob question
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@FATeknollogee said in XenServer 7: best practice: noob question:
@DustinB3403 said in XenServer 7: best practice: noob question:
For XS, if the Linux software RAID is better, why not just always recommend that option & why is this not a supported option?
Because Hardware RAID is more easily protected, with built in batteries.
What makes the Linux software RAID better?
Linux software RAID is better THAN WINDOWs software RAID. Linux software RAID is better because it has a two decade track record of being one of the best RAID implementations ever. It's used in many enterprise NAS and SAN devices as well. Windows software RAID has the same two decades of being so bad that the hardware RAID industry exists solely for it.
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@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
Linux software RAID would have the best performance is most cases. But the performance is trivial. It is much harder to set up and maintain which is why we and XenServer are not recommending it. For the SMB market, it just doesn't make sense because you need systems to be easily supportable and well under stood. That's why hardware RAID is the way to go in 99% of cases.
Easy answer... if you have to ask, the answer is definitely hardware RAID.
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@DustinB3403 said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
That is all dependent on how comfortable you are with software / hardware raid.
Even for software RAID experts, hardware RAID is easier.
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@scottalanmiller said in XenServer 7: best practice: noob question:
@DustinB3403 said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
That is all dependent on how comfortable you are with software / hardware raid.
Even for software RAID experts, hardware RAID is easier.
well yeah - it's practically plug and play - so few options.
Plus, in hardware RAID (assuming the chassis supports it) you get hot swap, something you don't get with Software RAID.
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@scottalanmiller said in XenServer 7: best practice: noob question:
Even for software RAID experts, hardware RAID is easier.
Ok, hardware RAID it shall be.
When using SSDs for VM storage, is there a performance difference RAID10 vs 5? (I realize RAID10 will cost you more per TB)
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@FATeknollogee said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
Even for software RAID experts, hardware RAID is easier.
Ok, hardware RAID it shall be.
When using SSDs for VM storage, is there a performance difference RAID10 vs 5? (I realize RAID10 will cost you more per TB)
There will be one, though it might be so small that you don't notice. But the reasons to use RAID 5 for SSDs are because rebuild times are so much faster the other issues with HDD RAID 5 are greatly reduced.
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@Dashrender said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
@DustinB3403 said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
That is all dependent on how comfortable you are with software / hardware raid.
Even for software RAID experts, hardware RAID is easier.
well yeah - it's practically plug and play - so few options.
Plus, in hardware RAID (assuming the chassis supports it) you get hot swap, something you don't get with Software RAID.
All enterprise software RAID has hot swap and always has. Only FakeRAID doesn't offer that and even that sometimes does. Hot swap is basically ubiquitous. Even ridiculous Windows software RAID has hot swap.
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@FATeknollogee said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
Even for software RAID experts, hardware RAID is easier.
Ok, hardware RAID it shall be.
When using SSDs for VM storage, is there a performance difference RAID10 vs 5? (I realize RAID10 will cost you more per TB)
Yes, RAID 10 is still faster and with lower latency. But with a good RAID controller, this is trivial and the cost doesn't make it make sense. Even with RAID 5 you can easily overrun your controller so there is no reason to spend money where the bottleneck doesn't exist.
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@DustinB3403 said
Since XenServer 7 has now quadrupled the space available, 32GB would be the minimum.
If you want to use the new partitioning in XS7, 32GB isn't enough. Has to be 64GB.
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@scottalanmiller said in XenServer 7: best practice: noob question:
Yes, RAID 10 is still faster and with lower latency. But with a good RAID controller, this is trivial and the cost doesn't make it make sense. Even with RAID 5 you can easily overrun your controller so there is no reason to spend money where the bottleneck doesn't exist.
What is your preferred RAID controller? Is the LSI family good enough?
For optimum performance in a RAID5 group, how many disks should be used ?
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@FATeknollogee said in XenServer 7: best practice: noob question:
What is your preferred RAID controller? Is the LSI family good enough?
LSI and Adaptec are best. Either is fine.
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@FATeknollogee said in XenServer 7: best practice: noob question:
For optimum performance in a RAID5 group, how many disks should be used ?
All of them
Not sure what more info you are looking for. You buy the right number that you need for your speed and capacity and then you put them all into a single RAID 5.
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@scottalanmiller said in XenServer 7: best practice: noob question:
@Dashrender said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
@DustinB3403 said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
That is all dependent on how comfortable you are with software / hardware raid.
Even for software RAID experts, hardware RAID is easier.
well yeah - it's practically plug and play - so few options.
Plus, in hardware RAID (assuming the chassis supports it) you get hot swap, something you don't get with Software RAID.
All enterprise software RAID has hot swap and always has. Only FakeRAID doesn't offer that and even that sometimes does. Hot swap is basically ubiquitous. Even ridiculous Windows software RAID has hot swap.
excuse me, I used the wrong term - I meant Blind swap - the lack of need to tell the OS to demount the drive before you pull it from the system.
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@scottalanmiller said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
For optimum performance in a RAID5 group, how many disks should be used ?
All of them
Not sure what more info you are looking for. You buy the right number that you need for your speed and capacity and then you put them all into a single RAID 5.
This was an issue when you had so few IOPs, but with SSD that's likely not your bottle neck anymore. So with SSD RAID 5, if three drives has enough capacity, just buy three drives, if not, buy more.
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@Dashrender said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
@Dashrender said in XenServer 7: best practice: noob question:
@scottalanmiller said in XenServer 7: best practice: noob question:
@DustinB3403 said in XenServer 7: best practice: noob question:
@FATeknollogee said in XenServer 7: best practice: noob question:
Does it have better performance & is it easier to setup?
That is all dependent on how comfortable you are with software / hardware raid.
Even for software RAID experts, hardware RAID is easier.
well yeah - it's practically plug and play - so few options.
Plus, in hardware RAID (assuming the chassis supports it) you get hot swap, something you don't get with Software RAID.
All enterprise software RAID has hot swap and always has. Only FakeRAID doesn't offer that and even that sometimes does. Hot swap is basically ubiquitous. Even ridiculous Windows software RAID has hot swap.
excuse me, I used the wrong term - I meant Blind swap - the lack of need to tell the OS to demount the drive before you pull it from the system.
Yes, now that software RAID generally lacks.
