Solved Get Large Disk Images on XenServer 6.5 on Local Filesystem?
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So back full circle.
Any idea's how to circumvent this?
As we can have HUGE locaclized storage repository for XenServer, but the Guest (Windows server VM) will only allow 2TB due to Windows VHD limitations...
so for those of us running large file servers (myself). this 2TB is an issue; its too small!
So would have to pool the disks together?
or rely on some large external storage device with NFS/SMB shares? This just adds to the infrastructure costs and possible failure points.
@Scale computing nodes...... same limitations I presume?
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@scottalanmiller said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
just storing music, home movies and such often requires far more than this (I have about 12TB for home.)
Ya, I have almost 2TB just in music.
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I'm not saying that 2TB or 2PB shouldn't be virtual, I'm saying that the amount presented out shouldn't need to be larger than 2TB (per share) for a virtual machine for the very reasons of usability and restore options.
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
I'm specifically saying present multiple 2TB shares out, unless you need more, in which case use an iSCSI target.
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@ntoxicator said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
So back full circle.
Any idea's how to circumvent this?
As we can have HUGE locaclized storage repository for XenServer, but the Guest (Windows server VM) will only allow 2TB due to Windows VHD limitations...
so for those of us running large file servers (myself). this 2TB is an issue; its too small!
So would have to pool the disks together?
or rely on some large external storage device with NFS/SMB shares? This just adds to the infrastructure costs and possible failure points.
@Scale computing nodes...... same limitations I presume?
You could switch to Xen and use a real image file. Scale won't have this limitation. It's KVM, which I'm also running, and with qcow2 the limit is something like 7 exabytes.
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@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
I'm not saying that 2TB or 2PB shouldn't be virtual, I'm saying that the amount presented out shouldn't need to be larger than 2TB (per share) for a virtual machine for the very reasons of usability and restore options.
I don't understand this at all. Why would you have benefits to small chunks of a single filesystem? I've heard this before but never heard of a reason for it.
Presented out obviously has to be larger than 2TB, that's not an option. That the parts that make up the large share should be made up of tiny pieces is standardly considered a mistake of 2005 era SAN design. Why do you feel that this industry accepted mistake of a decade ago should be made standard again today?
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in which case use an iSCSI target.
So you're saying to use Microsofts iSCSI initiator to connect a disk? I've been hit over the head before to suggesting that.
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@johnhooks said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
You could switch to Xen and use a real image file. Scale won't have this limitation. It's KVM, which I'm also running, and with qcow2 the limit is something like 7 exabytes.
Oh I know, I can make a pretty epic file server on the Scale HC3
It's way ahead for that. This is not for a system that I manage that I was looking for the answer. Yes, "real" Xen without XS limitations does this without a problem. And Scale HC3 does it without thinking. Why XS is introducing this problem is beyond me. -
@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
I'm not saying that 2TB or 2PB shouldn't be virtual, I'm saying that the amount presented out shouldn't need to be larger than 2TB (per share) for a virtual machine for the very reasons of usability and restore options.
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
He never said that. He said there are cases where you don't. And made good points, like with using Gluster/Ceph.
I'm specifically saying present multiple 2TB shares out, unless you need more, in which case use an iSCSI target.
And now you're limited to network throughput for your data.
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@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
What's the alternative method to file shares? And who is RobinHood? And why would we talk to someone that thinks that nothing should be virtualized?
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@scottalanmiller said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
@johnhooks said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
You could switch to Xen and use a real image file. Scale won't have this limitation. It's KVM, which I'm also running, and with qcow2 the limit is something like 7 exabytes.
Oh I know, I can make a pretty epic file server on the Scale HC3
It's way ahead for that. This is not for a system that I manage that I was looking for the answer. Yes, "real" Xen without XS limitations does this without a problem. And Scale HC3 does it without thinking. Why XS is introducing this problem is beyond me.Ha ya I was just answering for @ntoxicator. I don't understand this ridiculous limit. VHDX has been out for like 4 years.
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RobinHood specifically believes that you should never virtualize your file systems or work-loads.
Right now, my file server is "Virtualized" and "Virtualized Disk" coming from xenserver Storage Repository.
So with that being said, rather than having a virtualized file system; is to better having a networked SAN serving out SMB/NFS for data over network?
I'm just full circle and I apologize. #logic.
as if you do not have a need to Virtualize your file systems / shared. Then the Storage Repository needs would be significantly less; as would only need to Create Virtual Disks big enough for the server NEEDS. Then rely on network storage solutions for doing the SMB/NFS shares which attach to desktops / server?
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@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
I'm specifically saying present multiple 2TB shares out, unless you need more, in which case use an iSCSI target.
That's just crappy. Why would we accept that much failure? That's not a good answer at all. Using LVM to fix the 2TB limit is bad enough, this is far worse.
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@scottalanmiller said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
What's the alternative method to file shares? And who is RobinHood? And why would we talk to someone that thinks that nothing should be virtualized?
He's someone who I consider a troll over there. Who insisted that you don't virtualize massive storage needs.
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@scottalanmiller said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
What's the alternative method to file shares? And who is RobinHood? And why would we talk to someone that thinks that nothing should be virtualized?
He was on SW. He didn't say you shouldn't ever virtualize. He was dealing with multiple PB of data on Gluster. He was just making a point that you don't virtualize those types of systems, or large compute clusters like we have.
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@ntoxicator said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
So with that being said, rather than having a virtualized file system; is to better having a networked SAN serving out SMB/NFS for data over network?
You mean NAS, SAN can't do that. But the logic of limiting to 2TB here would affect a NAS as well as a NAS is just a file server. So if there is a belief that no one needs more than 2TB, then no NAS should be over 2TB either.
Which shows how much something is wrong. Obviously 2TB of storage should not be a limit any more than computers shouldn't need more than 640KB of RAM.
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@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
@scottalanmiller said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
@DustinB3403 said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
This is data administration, not system design. You have 2TB shares, if you need larger use another method. RobinHood specifically believes that you should never virtualize your file systems or work-loads.
What's the alternative method to file shares? And who is RobinHood? And why would we talk to someone that thinks that nothing should be virtualized?
He's someone who I consider a troll over there. Who insisted that you don't virtualize massive storage needs.
That's different than saying you don't virtualize workloads and filesystems. I don't agree with his statement, but just clarifying that that statement wouldn't apply here. This is still very small filesystems. We aren't nearly to massive yet.
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correction -- yes, a NAS network storage device. The SANITY!!
So, your saying with True HVM / XEN setup, you can present a virtual disk to Windows Guest operating system, which is greater than 2TB?
Limitation is strickly with XS 6.5 and prior, limiting to 2TB Virtual Disk sizes?
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@ntoxicator said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
correction -- yes, a NAS network storage device. The SANITY!!
So, your saying with True HVM / XEN setup, you can present a virtual disk to Windows Guest operating system, which is greater than 2TB?
Limitation is strickly with XS 6.5 and prior, limiting to 2TB Virtual Disk sizes?
Yes.
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@ntoxicator said in Get Large Disk Images on XenServer 6.5 on Local Filesystem?:
So, your saying with True HVM / XEN setup, you can present a virtual disk to Windows Guest operating system, which is greater than 2TB?
Oh yes, this limitation is purely because of the XenServer interface and is no way whatsoever a limitation of Xen. It's because XenServer uses the legacy Windows VHD file format that caps at 2TB for some archaic reason (that they use it, I know why it caps.) If they used the Xen native formats, this would be resolved.
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XenServer also uses EXT4 which is silly. XFS would be a better choice.
