Create vApp/VM in vCD using replicated datastore files

[derekf]

Hi there,

We're wanting to look at providing DR between to vCD virtual datacenters (in different physical datacenters) and I was wondering if the vCD VCO plugin could help.

I've a number of ways of replicating the data across (let's say we're replicating a LUN to make it simple) and I know we've seen example scripts that you can use within vSphere to scan a datastore and update inventories to bring those servers up on a different vSphere environment, but I want to do this in vCD.

Using various UI tools I know I can create the VMs in vSphere and then use the vCD cloud admin fuction to import the VM into vCD, but that's rather clunky (as well as being a pain in that it seems to do a clone/delete of the files when I say 'move' for the import).

We just don't see any products that can do that on the market at this time - SRS is supposed to bring in support for vCD at some stage in the future - but we have a real requirement now.

So the key questions are is there any 'clever' way when you have the vmdk and vmx files etc from VMs in an existing vCD environment replicated over to a SAN in a different vCD environment of using them for DR?

[tschoergez]

Hi!

this is a very intersting discussion and sounds like a perfect use-case for vCO 🙂

From the strategic perspective: Do you want to have a DR-site which 1-to-1 is replicated by the production site as "cold-standby"?

Or do you want to use the second-site even in production and "additionally" add the VMs/vApps/complete VDC structure of the first site "just-in-case"?

Depending on the answer to these questions you might want to keep the replicate the identity of the vApp as well, or you can go for a new identity of the vApp in the second site in a vDC structure just-like on the primary site....

Regards,

joerg

PS.: The same discussion comes in if you plan to use (or not to use but develop your own stuff) the Site Recovery Manager for plain vSphere inventory...

[cdecanini_]

Hi Derek,

Do you use different vCD instances ?

The ways I mocked this up is the following:

A set of workflows replicating orgs, VDCs, vApp Networks, Users, Catalogs.

A system replicating the VMDKs and making these accessible from the vCenter(s) backing up vCD (i.e SRM)

Import VM as a vApp workflow, recompose workflow to rebuild the vApp as the source one with the imported VMDK.

The difficulties for doing this are the dependencies. For example a vApp as depedencies on org networks, VDCs,  which have their own dependencies on the provider side (PVDC, external networks) that need to have similar capacities / IP allocations to have everything working as expected. To solve this I map each source entity to the created destination one and when copying I replace the links to these.

Other issues are the few things that cannot be copied via the API or Orchestrator such as the local user passwords. Now if you use a replicated LDAP on both sides you should not have this issue.

While I have good results so far I need to test this in a real life implementation vs the small labs I have access to ATM.

This is failover. Failback should also be considered.

Christophe.

[derekf]

Hi Joerg,

We're looking at having two physical sites with some vDCs in each site running production servers.  Some of these servers need to have DR on them to the other site.  We're happy with looking at cold failover for these servers and would probably put them in their own vDC as opposed to a vApp.

We can't just replicate the entire site unfortunately (as that would indeed simplfy things).

Derek...

PS - You're correct about SRS although at VMworld in Vegas we were told in an SRS futures that they would be integrating vCD in the future (but as always that's unfortunaly outside our timescales so we're looking at alternatives)

[cdecanini_]

Are you saying that within a same organization you have a VDC on site A and one on site B and need to clone the vApp from VDC A to VDC B using storage replication ?

If so this would be a lot easier to accomplish then the fully replicated vCD : import from vCenter & recompose from source vApp & imported VMs.

Christophe.

[derekf]

Hi Christophe,

Whilst in future it might be nice to think about 'cross vCloud' DR with different vCD instances, at present we're looking at a single vCD instance with, to keep it simple, a Provider vDC in each site.  We would then create Org vDCs in each of these where one would be production and one would be DR.  Some Org vDCs might not have DR and might be in either site, others might want DR.

Given the fact it would be the same vCD instance I'd not at this stage thought about workflows to replaciate orgs vDCs etc (but can see where we'd want that with multiple vCD instances), and was trying to focus on the VM recovery.

We've got the VMDKs being replicated (available through a number of options) and are working on how to get this into vCD.

Currently the only way we've found of doing this is, as you indicated in your post, creating them in vSphere and then importing them into vDC.  The problem with this in the initial testing we've done is that it involves a 'clone/delete' operation 'under the hood' which if you have many VMs with a lot of disk usage will significantly slow down the import into vCD in a DR scenario.

We're also considering how to do this in a DR and a DR test scenario.  a DR test scenario could work quite well if you import then into vCD using the copy (as opposed to move) method as it provides for continued replication of VMDKs etc whilst you're testing copies in vCD, however in DR I'm thinking that failback would probably need to be some form of manual process to reverse the failover.

You appear to be making good progress in this, but it looks like you're doing this with multiple vDCs - have you given any though to it using a single vDC?

Regards,

Derek...

[derekf]

Hi Christophe,

Our posts must have crossed.

Yes I am looking in the first instnace at having the same organisation with a vDC on each site (within a sinvle vCD instance) and needing to provide DR by replicating/cloning VMs over using some form of storage replication.

The aspect I'm trying to sort out is how best to get the VM into vCD and if import is the only option (as this seems to involve a copy operation under the scenes even if I specify 'move' when using the vCD UI

Regards,

Derek...

[cdecanini_]

There are 2 options I have implemented:

• hot clone of the vApp from one VDC to another one : http://www.vcoteam.info/learn-vco/vcloud-director-vapp-hot-clone.html
• storage copy of the VMs, import from vCenter

The first one requires 2 clones to allow for hot cloning.

The second one, besides the storage replication, should not require a clone for the import if the storage is part of the storage available of the PVDC (I have been told) but in the case of a vApp with more then one VM requires a clone for being recomposed (since the import only handles a single VM). If these are single vApp then the imported vApp can be modified to have the exact same properties as the original one.

Christophe.