Its not solving it, but you can run

echo 3 > /proc/sys/vm/drop_caches

to release some of the cache again, without interfering with running processes.

[root@host2 ~]# free -m
total used free shared buff/cache available
Mem: 15958 3308 158 8 12491 2355
Swap: 1023 177 846
[root@host2 ~]# echo 3 > /proc/sys/vm/drop_caches
[root@host2 ~]# free -m
total used free shared buff/cache available
Mem: 15958 3308 2598 10 10051 2751
Swap: 1023 177 846

A test was recently pushed to XTF's repository which may crash a host whose hardware is vulnerable to XSA-304 (hardware vulnerability related to EPT superpages).

There are two modes in Xen regarding EPT superpages, fast vs secure, and XCP-ng defaults to fast due to the big performance hit secure would have by default on affected hardware. The vulnerability may allow an HVM guest to crash the host, and this is what the test demonstrates.

I've updated the small Xen testing guide above with instructions to switch to secure mode before running the tests, if you want to avoid the crash in case your host is vulnerable.

@wyatt-made No such thing is known. I just haven't checked the compatibility yet.

When you boot in UEFI mode, press "e" to edit the boot command line, you have a line to change the memory for dom0.

I did the manual installation via the XVA. It worked for me.

@Pyroteq Currently I am running my plex server via TrueNAS scale with HW transcoding. So I don't need it with XCP-NG anymore... 🙂 But for the people who do need it, this can be useful to them.

Perfect! Now expect all of this but in a simple wizard in the UI, that will be a great tool for everyone who want to make the migration (and we hope to get a decent share of those users with our new support bundle)

@akurzawa said in Extrlemy slow backup speec = about few MB/s:

@nikade said in Extrlemy slow backup speec = about few MB/s:

Maybe you saw the same thing I did - I also had major issues with backups. Then in the summer of 2019 I upgraded our XOA (Yes, we have the paid version) and everything was going 3-4x times faster. Must have been some major improvement in the XOA code.

So maybe some official info that if you have XO from source Your backup speeds will be as low as 3-4 MB/s? Or what?

Sorry if I was unclear - XOA is built from the same sources so there is no difference in that aspect.
All tho, there was a big performance issue regarding backups which was resolved.

I am using XO from sources in my "private" infrastructure and I can assure you there are no "limits" on purpose.

How about doing your own matrix?

I'm not sure Unitrends is supporting XCP-ng. Please refer to your backup vendor.

Current backup solutions claming to support XCP-ng: https://xcp-ng.org/docs/backup.html

@olivierlambert thank you for your comment.

We always try to work with Citrix ("XenServer" division now), to push things upstream and manage to get it merged.

@chrisarzu

You're very welcome. My solution to the similar problem I'd had was to set up a couple of internal systems as NTP servers so that I always had something with the right time and static IP addresses and pointed everything needing NTP at them.

@dvdhngs

install onto (mdadm/ZFS) RAID 10: no

to use (mdadm/ZFS) RAID 10 as SR: yes, of course!

Hi ! We are experiencing these kind of problems because we activated Continous Replication and frequency was way too low.

Now I want to eliminate all those files in the chain, can I do it manually from XCP-NG Center or XOA ?

Thanks !!!

c2aa1fb3-2ed2-41cf-b242-e2a23e6832e4-image.png

@jokurinopoloski I reviewed your PR!

Thanks for the contribution 🙂

@danp said in XCP-ng 7.5.0 final is here:

@dblogic said in XCP-ng 7.5.0 final is here:

Just tried updating our pool and after updating the master had failed migration of VM (Ubuntu) and then was unable to get VM to start (Missing VDI error). Only solution was to roll master back to 7.4 and everything working again.

I ran into a similar situation when I upgraded to 7.5 this week. Did you check to see if there was a non-existent ISO mounted in the CD rom for the VM in question?

Thank you. That was my problem. I gave cd empty. Everything works.

Actually, looks like I had already written something about it in the Updates Howto: https://github.com/xcp-ng/xcp/wiki/Updates-Howto#a-special-word-about-xcp-ng-75-76-and-live-migrations

anyone can request a change in https://github.com/xcp-ng/xenadmin/issues 🙂