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Dundee Alpha 2 Released

I am pleased to announce that today we have made available the second alpha build for XenServer Dundee. For those of you who missed the first alpha, it was focused entirely on the move to CentOS 7 for dom0. This important operational change is one long time XenServer users and those who have written management tooling for XenServer should be aware of throughout the Dundee development cycle. At the time of Alpha 1, no mention was made for feature changes, and with Alpha 2 we're going to talk about some features. So here are some of the important items to be aware of.

Thin Provisioning on block storage

For those who aren't aware, when a XenServer SR is using iSCSI or an HBA, the virtual disks have always consumed their entire allocated space regardless of how utilized the actual virtual disk was. With Dundee we now have full thin provisioning for all block storage independent of storage vendor. In order to take advantage of this, you will need to indicate during SR creation that thin provisioning is required. You will also be given the opportunity to specify the default vdi allocation which allows users to optimize vdi utilization against storage performance. We do know about a number of areas still needing attention, but are providing early access such that the community can further identify issues our testing hasn't yet encountered.

NFS version 4

While a simple enhancement, this was identified as a priority item during the Creedence previews last year. We didn't really have the time then to fully implement it, but as of Dundee Alpha 2 you can specify NFS 4 for SR creation in XenCenter.

Intel GVT-d

XenServer 6.5 SP1 introduced support for Intel GVT-d graphics in Haswell and Broadwell chips. This support has been ported to Dundee and is now present in Alpha 2. At this point GPU operations in Dundee should have feature parity to XenServer 6.5 SP1.

CIFS for virtual disk storage

For some time we've had CIFS as an option for ISO storage, but lacked it for virtual disk storage. That has been remedied and if you are running CIFS you can now use it for all your XenServer storage needs.

Changed dom0 disk size

During installation of XenServer 6.5 and prior, a 4GB partition is created for dom0 with an additional 4GB partition created as a backup. For some users, the 4GB partition was too limiting, particularly if remote SYSLOG wasn't used or when third party monitoring tools were installed in dom0. With Dundee we've completely changed the local storage layout for dom0, and this has significant implications for all users wishing to upgrade to Dundee.

New layout

The new partition layout will consume 46GB from local storage. If there is less than 46 GB available, then a fresh install will fail. The new partition layout will be as follows:

  • 512 MB UEFI boot partition
  • 18 GB dom0 partition
  • 18 GB backup partition
  • 4 GB logs partition
  • 1 GB SWAP partition

As you can see from this new partition layout that we've separated logs and SWAP out of the main operating partition, and that we're now supporting UEFI boot.

Upgrades

During upgrade, if there is at least 46 GB available, we will recreate the partition layout to match that of a fresh install. In the event 46GB isn't available, we will shrink the existing dom0 partition from 4 GB to 3.5 GB and create the 512 MB UEFI boot partition.

Downloading Alpha 2

 

Dundee Alpha 2 is available for download from xenserver.org/prerelease

Storage XenMotion in Dundee
Preview of XenServer Administrators Handbook

Related Posts

 

Comments 42

Tim Stephenson on Tuesday, 14 July 2015 20:17

46Gb+ seems very large for Dom0 :/

We're running XenServer on a set of Dell Poweredge R630's s equipped with dual 16Gb SD card boot disks; releasing all local disks / SSDs for Xen VMs.
Given the 46gb dom0 storage requirement, it sounds like we're not going to be able to upgrade our machines to this release??

Is this likely to change before release?

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46Gb+ seems very large for Dom0 :/ We're running XenServer on a set of Dell Poweredge R630's s equipped with dual 16Gb SD card boot disks; releasing all local disks / SSDs for Xen VMs. Given the 46gb dom0 storage requirement, it sounds like we're not going to be able to upgrade our machines to this release?? Is this likely to change before release?
Tim Mackey on Tuesday, 14 July 2015 20:26

It's not 46GB for dom0, but 46GB for all storage dedicated to XenServer itself (dom0 is only 18GB). I hear you about the SD card boot. For an upgrade on your setup it'll *should* be fine, but for a fresh install it will bail. I've had a side project for a while to get SD card working properly, and have now added figuring out a workable way to support 8GB USB and higher under this new model. I may want to compare notes with you on that effort.

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It's not 46GB for dom0, but 46GB for all storage dedicated to XenServer itself (dom0 is only 18GB). I hear you about the SD card boot. For an upgrade on your setup it'll *should* be fine, but for a fresh install it will bail. I've had a side project for a while to get SD card working properly, and have now added figuring out a workable way to support 8GB USB and higher under this new model. I may want to compare notes with you on that effort.
Tobias Kreidl on Tuesday, 14 July 2015 20:45

First off, this is fantastic news, regarding what's mentioned (NFSv4, thin provisioning on LVM, bigger partition space, CIFS storage, etc.) but also as I understand it, there are a number of storage Xenmotion enhancements that will allow for both running and halted VMs to be copied and left in various states. Above all, the thin provisioning of LVM storage repositories will open up some very exciting possibilities for handling efficient snapshot operations, in particular for dealing with incremental backup and restore options.

Congratulations to all who contributed to these collected efforts!

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First off, this is fantastic news, regarding what's mentioned (NFSv4, thin provisioning on LVM, bigger partition space, CIFS storage, etc.) but also as I understand it, there are a number of storage Xenmotion enhancements that will allow for both running and halted VMs to be copied and left in various states. Above all, the thin provisioning of LVM storage repositories will open up some very exciting possibilities for handling efficient snapshot operations, in particular for dealing with incremental backup and restore options. Congratulations to all who contributed to these collected efforts!
Guest - Jeff Riechers on Tuesday, 14 July 2015 20:51

I would like to see folder support for the CIFS iso storage. Some clients group them based on vendors and versions.

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I would like to see folder support for the CIFS iso storage. Some clients group them based on vendors and versions.
Tobias Kreidl on Tuesday, 14 July 2015 21:29

Is by any chance ext4 now supported?

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Is by any chance ext4 now supported?
Guest - John on Wednesday, 18 November 2015 03:17

I would Also appreciate an answer to this as it's just more cost effective to toss a 120GB SSD at $60 in for the boot drive considering the boot times.

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I would Also appreciate an answer to this as it's just more cost effective to toss a 120GB SSD at $60 in for the boot drive considering the boot times.
Guest - Herman Johnson III on Tuesday, 14 July 2015 22:01

Can I manage XenServer 6.5 SP1 with XenCenter 6.6.80.2642?

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Can I manage XenServer 6.5 SP1 with XenCenter 6.6.80.2642?
Andrew Halley on Wednesday, 22 July 2015 14:24

In general - XenCenter is backwards compatible with all previous versions of XS. Henec - this should work without problems.

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In general - XenCenter is backwards compatible with all previous versions of XS. Henec - this should work without problems.
Sébastien RICCIO on Wednesday, 15 July 2015 04:03

Oh yeah, great news, thanks a lot for your efforts !

It was a good idea to raise the dom0 disk space, it is getting quite tricky to apply patches without fighting with a filled dom0 !

Great news too for the NFS4 official support. Talking about this, will it be now possible to give mount options at the NFS SR creation, such has using hard instead of soft (to , for example, avoid VM getting read only in case of interruption of connectivity within the hosts and the storage filer).

In XenCenter we can specify options but they are ignored (I've checked the current NFS.py and I found nowhere that these options were used in the code...)

Thanks again for everything.

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Oh yeah, great news, thanks a lot for your efforts ! It was a good idea to raise the dom0 disk space, it is getting quite tricky to apply patches without fighting with a filled dom0 ! Great news too for the NFS4 official support. Talking about this, will it be now possible to give mount options at the NFS SR creation, such has using hard instead of soft (to , for example, avoid VM getting read only in case of interruption of connectivity within the hosts and the storage filer). In XenCenter we can specify options but they are ignored (I've checked the current NFS.py and I found nowhere that these options were used in the code...) Thanks again for everything.
Guest - fbifido on Saturday, 01 August 2015 03:29

Will it do NFS4 VAAI-NAS (hardware acceleration)?

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Will it do NFS4 VAAI-NAS (hardware acceleration)?
Guest - Keerthiraja on Wednesday, 15 July 2015 06:39

Is the Dundee Supprt the VxLAN implementation ready.

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Is the Dundee Supprt the VxLAN implementation ready.
Tim Mackey on Wednesday, 15 July 2015 14:29

@Keerthiraja

XenServer 6.5 and higher has an ovs capable of running VxLAN. You would need to provide a control plane to configure it. Citrix doesn't currently offer commercial support for such a configuration, but if you are willing to investigate the control plane aspect, I'm certain others would appreciate your efforts.

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@Keerthiraja XenServer 6.5 and higher has an ovs capable of running VxLAN. You would need to provide a control plane to configure it. Citrix doesn't currently offer commercial support for such a configuration, but if you are willing to investigate the control plane aspect, I'm certain others would appreciate your efforts.
Guest - Tim Stephenson on Wednesday, 15 July 2015 07:51

Sounds great Tim - would be very keen to hear more!
We're currently running with local storage in our R630's ahead of moving to a 10GbE / iSCSI setup in a few months. At that point, the R630 hosts will be diskless bar the dual SD cards. Would be preferable not to replace the SD's but if needs must....
Anything I can do to help, just shout.
Tim

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Sounds great Tim - would be very keen to hear more! We're currently running with local storage in our R630's ahead of moving to a 10GbE / iSCSI setup in a few months. At that point, the R630 hosts will be diskless bar the dual SD cards. Would be preferable not to replace the SD's but if needs must.... Anything I can do to help, just shout. Tim
Stephen Turner on Wednesday, 15 July 2015 08:36

@Herman: Yes, XenCenter will manage all supported versions of XenServer.

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@Herman: Yes, XenCenter will manage all supported versions of XenServer.
Herman Johnson III on Wednesday, 15 July 2015 18:17

Thank you. Just to be clear, XenCenter 6.6 is safe to use in production or should I just stick with the 6.5 version to manage XenServer 6.5?

Thanks,

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Thank you. Just to be clear, XenCenter 6.6 is safe to use in production or should I just stick with the 6.5 version to manage XenServer 6.5? Thanks,
Tobias Kreidl on Wednesday, 15 July 2015 21:14

@Herman: I have been running multiple installs of the Dundee Alpha 2 version of XenCenter for a couple of days now with no problems at all with XS 6.5 SP1 and Dundee Alpha 1 pools managed under it.

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@Herman: I have been running multiple installs of the Dundee Alpha 2 version of XenCenter for a couple of days now with no problems at all with XS 6.5 SP1 and Dundee Alpha 1 pools managed under it.
Stephen Turner on Thursday, 16 July 2015 08:34

@Herman: It should work fine. However, obviously it's not yet received the amount of testing that a released version has, so there are likely to be more bugs, and Support won't take calls on it!

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@Herman: It should work fine. However, obviously it's not yet received the amount of testing that a released version has, so there are likely to be more bugs, and Support won't take calls on it!
Martin Kralicek on Wednesday, 15 July 2015 08:57

Very cool :) I am very happy to see "Thin Provisioning on block storage"
But, will be possible to transfer current VM from thick to thin? Or we will have to re-create SR and VHD as well?
Thanks for your hard work :)

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Very cool :) I am very happy to see "Thin Provisioning on block storage" But, will be possible to transfer current VM from thick to thin? Or we will have to re-create SR and VHD as well? Thanks for your hard work :)
Tim Mackey on Wednesday, 15 July 2015 14:33

@Martin

I'll wait for someone more familiar with the implementation to comment on reality, but this is my expectation....

Since we currently have Storage XenMotion which can move between all storage types, including local storage provisioned thinly, I would expect a VM migration between the current thick block storage to a new thin block storage would work (or if not in this Alpha, in a future Alpha/Beta). Converting an existing SR from thick to thin I wouldn't expect to work.

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@Martin I'll wait for someone more familiar with the implementation to comment on reality, but this is my expectation.... Since we currently have Storage XenMotion which can move between all storage types, including local storage provisioned thinly, I would expect a VM migration between the current thick block storage to a new thin block storage would work (or if not in this Alpha, in a future Alpha/Beta). Converting an existing SR from thick to thin I wouldn't expect to work.
Stephen Turner on Thursday, 16 July 2015 08:37

@Martin @Tim: We are going to try to do conversion from thick to thin. Not written yet, so no promises.

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@Martin @Tim: We are going to try to do conversion from thick to thin. Not written yet, so no promises.

About XenServer

XenServer is the leading open source virtualization platform, powered by the Xen Project hypervisor and the XAPI toolstack. It is used in the world's largest clouds and enterprises.
 
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