@tjkreidl We don't need performance, but we do need to test how XCP-ng pools, networking, migration, live migration, backup, import from VMware and so on work. It's just a playground where we can have relatively many XCP-ng hosts, but it's not about performance, it's about efficiency and low requirements, because it's just a playground where we learn, validate how things work, and prepare the process for the final migration from VMware to XCP-ng. We originally had two R630s ready for this, then 4, but that would have been unnecessary, given the power consumption, to have physical hypervisors, so in the end we decided to virtualize it all. Well, on ESXi it's because XCP-ng works seamlessly there in nested virtualization.

@tjkreidl In the end, everything turned out completely different. In order to make the lab as efficient as possible, we decided to virtualise it. That is, to run XCP-ng hosts as guests on a dedicated hypervisor. This allows us to efficiently turn virtualized hosts on and off, change their CPU counts, etc.

The only problem is that the current version of XCP-ng, or the version of Xen used, does not yet support nested virtualization, so the entire XCP-ng virtual lab "sits" on an ESXi hypervisor.

@manilx Thanks, how simple! I confused myself by thinking of "Block" as a noun, not a verb imperative, being influenced by the NBD term

Hi, what exactly is the purpose of the "Block migration" setting on the Advanced tab of the VM configuration?

I tried to look it up in the documentation at https://docs.xen-orchestra.com, but I had no luck finding it there. Thank you in advance for the explanation.

Hi, I was wondering if it is possible to configure auto-start order of the virtual machines and set related delays. Something similar to this configuration available within an ESXi server:

Regarding my tests and other post on this forum I got the impression that in a single-host environment (lab/test/home env.) it is not possible, that "Start delay (seconds)" option available on the VM´s Advanced tab has no effect in such case (It seems that the VM is started immediately after the host boots up, even if a delay is configured.).

Did I miss something? Thanks a lot in advance for the explaining how this works with XCP-ng and Xen Orchestra.

@tjkreidl Hello, I have two identical Dell R630 servers (BIOS 2.19.0) each with a pair of Intel E5-2680 v4 CPUs in my lab where I am testing deployment scenarios. In the lab, performance is not important, but instead I want to minimize power consumption. Ideally to be able to switch performance "profiles" without having to reboot the servers and toggling settings in the BIOS. Thanks for the link to the article, useful tips and advice there!

Hi,
are there any configurable options for a basic power management policy similar to ESXi?

Restarting the toolstack on the host resolves the CPU count issue in the Stats view.

@florent Can you please provide some summary on backup setup versus compression versus remotes configuration?

@frank-s This confirms my observations and tests that for compression to be active, data blocks must be enabled for remote.

@frank-s Do you have the "data block" option enabled for remote or not?

(The idea behind is to have both a compressed delta backup (the backup repository itself is backed up to another location via vpn, so the size of the backup matters) and the fastest possible restore option.)

In addition, I have verified that if the option "Store backup as multiple data blocks instead of a whole VHD file" is enabled, the restore from the data blocks structure takes about 2-3 longer than from the .vhd if this option is disabled (I tested the health check restore).

At least the first backup, i.e. the full backup (and maybe every key full backup milestone later) does not look like it is compressed. If the "Store backup as multiple data blocks instead of a whole VHD file" option is off, a .vhd of 116 GiB is stored, if it is on, the whole data block structure is only 67 GiB.

If I understand correctly, for compression to work for Incremental (Delta) backup, remote storage must have the option "Store backup as multiple data blocks instead of a whole VHD file" enabled, otherwise vhd files are stored without compression. Is that right?

@olivierlambert said in Compressed backups:

Compression is enabled by default for incremental backups.

Hi, if I configure Delta Backup and run a backup for the first time, a full backup of the affected virtual machines is performed. This initial full backup is also compressed?

@abudef said in Managing disks and storage in the XO GUI:

create a RAID 5

Or rather ZFS, but I guess it doesn't matter, it's more about the GUI management option in general...

Sure, for example I have 4 disks in my host server ready for local storage. I would like to list them in the GUI and create a RAID 5 from them, without having to connect to the host server console and use the mdadm tool. And I would like to select this RAID to create local storage again by selecting it without having to specify the device path.

Hi, I would like to ask if there is any plan for more advanced GUI support for managing local storage on individual hosts. I mean a comfortable management of disk devices, so that the preparation for mounting local storage does not have to be done in the command line with Linux tools, for example preparing and managing disks connected to a raid etc.

@olivierlambert So there are basically no dramatic architectural differences in the individual hypervisors in this regard?