VMs exported with 5.1 don't start with 5.0

[butterblume]

Hi all,

Is there a way to get VMs running under 5.0 which where exported(build) with 5.1.6? We build VMs with packer and 5.1.6. Those boxes don't run under 5.0.26. I heard that this is addressed in 5.0.27?

Thx, butterblume

[michaln]

Given the scarcity of time machines, it is normal that older software can't handle data files created by newer software.

[mpack]

Perhaps a little more detail on "don't run" is called for.

[butterblume]

In a box built (exported) with 5.1 and run (imported) with 5.0 the network interface doesn't come up. More details can be found in viewtopic.php?f=7&t=78840

And yes, I should use 5.1 and not 5.0. And I do. But we provide to our customers Vagrant developer boxes for our product and neither can I tell them "you must use 5.1" nor can I know which version they are using. So we try to be compatible at least one version backwards which is 5.0. Since 5.0 can't start 5.1 boxes, we are in a bit of a dilemma.

[socratis]

There are a couple of things worth mentioning related to your problem:

1. In the thread that you linked to, the problem seems to be with the "import" functionality of VirtualBox 5.1.x, not the "export" of 5.1.x or the "import" of 5.0.x. So, I don't see the connection. Clarification of what doesn't work is essential I believe.
2. "And yes, I should use 5.1 and not 5.0.": I think you have it wrong. You should be using 5.0.x if you want to support 5.0.x. Usually programs try to make sure that are backwards compatible, i.e. have an upgrade path. Or, you should be using both versions if you want to support both.
3. "Since 5.0 can't start 5.1 boxes": Why not? I can open 5.1.x VMs with versions as back as VirtualBox 4.3.x, so I don't know why you're having this problem. Errors? Logs? Diagnostics? Anything?
4. In every post you've made you've been mentioning Vagrant. You know that Vagrant is a program that relies on VirtualBox but modifies its configuration files in unknown ways to us. It is not supported on these VirtualBox user forums, they have their own Vagrant support channels. Are you are having this problem with a standalone version of VirtualBox, i.e. no 'packer' or 'Vagrant' involved?

[butterblume]

@socratis: Yes, you're right. That was a very poor post of me and I'm sorry about that. I'll need some time to rebuild the setup and collect all necessary data. As soon as I have all data I'll post again.