Feature Request / Community Input – VM Boot Order & Delayed Startup

[Cygace]

Hello everyone,

I’m currently deploying a complete infrastructure for a client who previously used Hyper-V, where we could easily configure a VM boot order as well as startup delays between VMs.
This ensured a clean sequence:
1. XOA
2. Domain Controller
3. Application servers, etc.

⸻

What I have verified so far

I contacted the official XCP-ng / XOA support, and they confirmed that this functionality does NOT currently exist, even on the paid (Premium) version of XOA.

They also confirmed that:
• There is no native way to set a boot priority in XCP-ng
• There is no parameter such as order= or delay= in xe vm-param-set
• XOA does not provide a UI for this either
• The orchestration engine does not currently support dependent startup

⸻

What I’m asking the community

Before I build something custom (scripts, hooks, cron jobs, etc.), I would like to know:

Has anyone implemented a reliable way to:
• Force a boot order for VMs
• Introduce a configurable delay between VM startups
• Ensure XOA starts first, then the Domain Controller, then other servers

Is there perhaps:
• A community script
• A known workaround
• A XenAPI trick
• Or an unofficial feature hidden somewhere?

⸻

Environment
• XCP-ng host
• XOA Premium
• ~5 VMs (DC, financial software, POS system, XOA itself, etc.)
• Need clean deterministic startup order after host reboot or power outage

⸻

Any insight or community solutions would be greatly appreciated!
This is something my client relied on in Hyper-V, so I’m trying to replicate the behavior in XCP-ng as cleanly as possible.

Thanks in advance!

[olivierlambert]

Hi,

You can use vApp for that.

[Cygace]

said in Feature Request / Community Input – VM Boot Order & Delayed Startup:

Hello everyone,

I’m currently deploying a complete infrastructure for a client who previously used Hyper-V, where we could easily configure a VM boot order as well as startup delays between VMs.
This ensured a clean sequence:

1. XOA
2. Domain Controller
3. Application servers, etc.

⸻

What I have verified so far

I contacted the official XCP-ng / XOA support, and they confirmed that this functionality does NOT currently exist, even on the paid (Premium) version of XOA.

They also confirmed that:
• There is no native way to set a boot priority in XCP-ng
• There is no parameter such as order= or delay= in xe vm-param-set
• XOA does not provide a UI for this either
• The orchestration engine does not currently support dependent startup

⸻

What I’m asking the community

Before I build something custom (scripts, hooks, cron jobs, etc.), I would like to know:

Has anyone implemented a reliable way to:
• Force a boot order for VMs
• Introduce a configurable delay between VM startups
• Ensure XOA starts first, then the Domain Controller, then other servers

Is there perhaps:
• A community script
• A known workaround
• A XenAPI trick
• Or an unofficial feature hidden somewhere?

⸻

Environment
• XCP-ng host
• XOA Premium
• ~5 VMs (DC, financial software, POS system, XOA itself, etc.)
• Need clean deterministic startup order after host reboot or power outage

⸻

Any insight or community solutions would be greatly appreciated!
This is something my client relied on in Hyper-V, so I’m trying to replicate the behavior in XCP-ng as cleanly as possible.

Thanks in advance!

Hello Olivier, vApp ???

What do you mean ?

[Pilow]

@Cygace in advanced settings of VMs
there is

I know at scale it is not easy with 100+ VMs but...
try to put 40s for all VMs, except 20s for domain controller, and 0 for XOA ?

that will not change start order as you think it, but in case of a full restart should do the job ?

[olivierlambert]

https://docs.xcp-ng.org/appendix/cli_reference/#appliance-commands

[Pilow]

@olivierlambert hmmm could we consider an appliance as a "group of VMs" ?

if appliance is destroyed, what about the underlying VMs ? still there ?

[olivierlambert]

Yes, it's a way to group VMs and to get boot prio for them.

[Pilow]

@olivierlambert nice !
a new discover...

no way to manage by UI in xo5/xo6 AFAIK ?

[olivierlambert]

Nope, it was never a priority vs all the rest. But the API is there, so it's something we could do at some point. Adding @gregoire in the loop so we are sure it's somewhere in the backlog.

[Cygace]

Hello everyone,

We have use now XCP-ng Standalone (paid version) with a single host and about 8 VMs.

After opening a ticket with support, I received confirmation that there is currently no built-in feature in XCP-ng or XOA (even Premium) to control VM boot order or per-VM startup delays.

XOA’s Auto-Power-On option does not offer sequencing or delays.
The documentation mentions “appliances”, but even after reviewing that I don't understand how It can help me.

What I need is very simple:
1 Host 1 pool, around 8 VMs.
I need them to auto-start after a host reboot in a specific order, with a delay between each VM (e.g., XOA → Domain Controller → other servers, with 30 seconds delay).

If this cannot be done natively for now, I’ll create a startup script, but before doing that I would really appreciate feedback from others in the community who may have solved this.

Thanks in advance for any advice or ideas!

[olivierlambert]

Create an appliance with all those VMs and configure the order and delay inside it.