Thank you all seems I've got my answer, will go core

@olivierlambert you're a grandmaster, never even considered that It seems to be stuck but likely firewall will have a look thank you

Just checking if there is any impact in XCP-NG and / or XO that may be impacted by the log4j vulerability? Not sure if some of the API's uses java?

@olivierlambert Perfect, setting the parameter on both the VM and the snapshot resolves the issue. I am able to continue backups Thank you both for helping!

We're planning this for tomorrow so any last minute thoughts will greatly be appreciated.

We have a NAS we want to share between hosts. There are 3 hosts in total. 2 of these are our "primary" hosts, each has 2 SR's.

We want to setup a CR backup to replicate Server 1 SR 1 to Server 2 SR2 and Server2 SR1 to Server 1 SR2 as part of a availability job. I have opened a support ticket and Yannick recommends we keep the 2 hypervisors in their own pools, however, he says it is indeed possible for us to create a replication job the way we envision below. The problem is just that we're going into production with this so curious if there are others doing something similar and if there is a chance we may run into unknown issues down the line? As I now know one cannot simply remove a host from a pool without destroying all vm's on the local SR, I am worried that we go ahead with this and we end up with a case where the CR does not work as planned and at that time have to figure out a way to reset and do over.

So, in a nutshell, is there a chance we may run into issues down the line? Should we rather keep the servers in seperate pools and only have 1 of the 2 hypervisors have access to the NAS and if the hypervisor goes down we can then figure out how to move it to the other hosts?

Thank you @olivierlambert

So in principle there would be no concern with the design of having 2 hypervisors each with 2x local storage repositories each, and each replicating it's storage to another hypervisor in the same pool? Sorry for being anal about this, as we're going into production with this I'm just trying to be prepared for some strange scenario that can occur? Is this a common practice?

Also, if I do CR, how do I avoid 2 VM's being backed up as we only want to backup the primary / running VM?

We're busy migrating from numerous hypervisors to 2 primary ones with each hypervisor (XCP) having 2 separate storage repositories into a single pool so that they can share a common NAS. We want to setup continuous replication from server A SR1 > server B SR2 and same server B SR1 > server A SR2. This will also allow for the hosts to share a common NAS.

Are there any risks or is this frowned upon to replicate a VM within the same pool? I recall having an issue in the past with a duplicate GUID issue, but not sure if that was applicable to this problem?

The XO team is also bringing the magic!

I know I cannot migrate / CR from a newer to older hypervisor version, so not sure if same applies for older to newer migration / CR

Server A is slightly older than Server B (XCP version) - Can Server A CR a VM to Server B and will it start?

We're backing up to a NFS with TrueNAS. I am now replicating some of the backups to an offsite truenas so that we have some offsite redundancy. Our XO is hosted in the same building as the primary TrueNAS backups. Say something happens to the building and I need to make use of the offsite backups, would I be able to create a new XO instance offsite and "import" the backups made on the offsite backups (so the backups of the backups)? What would be needed to achieve this?

As an example, our XO instance is backed up to the truenas NFS which is replicated offsite. Can I create either a new XO instance and import the backup files from the offsite backup to start restoring VM's as part of a DR process or what process would one need to follow to make use of the VHD files that are backed up?

@olivierlambert I noted now when removing the host that is says it removes all VM's from the local storage and reboots. When you add the host to a pool, you can simply shutdown all VM's on the host, why does it remove vm's if you want to remove the host from a pool?

@olivierlambert although the topology of the servers are the same (each server has 2x CAT6 1GB which needs to act as a bond and 1x 10GB Fibre interface), I am having a tough time to figure out how the networks are "ordered"

As example, host 1 (master) has a bonded port (called WAN which is the WAN input for VMS). It shows 2 Gb/s as expected (I created the bond a while ago prior to the server becoming a master in a pool) and I created a new "network" called 10GBLAN which is effectively just a renamed version of eth4

However looking at the slave, although the topology is the same, it would appear that the physical server 10GB lan is plugged into eth5, not eth4 as per the master. As you can now see within the screenshot, the 10GBLAN is disabled on the slave server. I am not sure how to resolve this without sending someone to the DC to go move the cable which feels like overkill

I can only assume that the 10GBLAN is now not considered invalid for the pool?

Having said that, I am considering the move the host out of the pool (but have some work as I have a couple of VM's now running on shared NFS storage within the pool so first need to move them). I ran into an issue yesterday that I cannot move a VM from out of the pool into this pool (I get a duplicate_vm) error. I do replicate the VM using CR to the master in this pool, so assume that because I have a CR VM it is seeing it as a duplicate. I reviewed another post but was not sure if it's applicable to us (I reviewed https://xcp-ng.org/forum/topic/3262/migrating-vm-fails-with-duplicate_vm-error?_=1659370548388 and see someone ran into something similar but could not figure out how they fixed it)

So I might move the host out of the pool (it's only 2 hosts so far) and maybe keep the failover server completely seperate and add the other hypervisors to create a pool.

Is it possible to remove a host from a pool and set it back to be managed by it's own?