Migrate Data from Virtual to Physical

JockVSJock

I didn't see any hits online for this, so I thought I would start here.

Maybe its more of a storage question then Virtualization...

I've been tasked with migrating a virtual server to a physical server. Its around 28 TB of data and the reason for this is due to alot of rules and regulations that are being pushed down from above.

My concern is moving data that currently lives on RHEL6 (ext4 file system) that is mapped to LUNs/Data Stores/WWIDs and then all of the sudden its finding itself on physical storage, which will be RHEL6 (ext4 file system). Maybe I'm overthinking this...

Right now I'm in the planning stage, however I've never been faced with anything like this before, so there is alot to consider before kicking this project off.

Lexluethar

Can you vmotion the server over to it's own hypervisor that has the recommended settings they are wanting?

We have run into the same issue on a few applications, the vendor would not support virtualization (shocking i know) so we compromised and said okay, it's going to be in vmware as a virtual server but it will have all of the available resources on it's own hypervisor.

JockVSJock

Lexluethar wrote: »

Can you vmotion the server over to it's own hypervisor that has the recommended settings they are wanting?

I know you can vMotion P2V. However I didn't know that you could go from V2P?

I'm honestly thinking of setting up the new physical and then using rsync to move from the Virtual to Physical. I don't believe that Redhat has a migration tool.

I would find a sample first and test it and then if it worked out ok, then move 28 TB in stages.

Lexluethar

No i wasn't talking about a V2P, i was simply saying you could give the virtual machine it's own hypervisor, which essentially would be the same as putting linux right on the hardware. Yes i realize there is a difference but vmware makes absolutely sure that difference is negligible.

I don't know what the higher ups are demanding - i'm just giving you another option. We had a similar situation and the compromise was running the server on its own server (vsphere instance) which means it gets all resources but can still be managed by vcenter.

techfiend

Relatively easy with windows and I can't believe there isn't a few different ways to do it in linux. Linux is controlled by files afaik and an rsync should do along with some grub configuration.

I had this 'physical thing' at my last position where all critical services must have a physical alternate. I found microsoft documenting this as best practices in the early 2000's when virtualization was pretty fresh. Unfortunately it's carried over in some companies.

jibbajabba

We encountered too many issues when trying to migrate a virtual Linux server to physical, especially due to the storage configuration. As you suggested, rebuild and rsync is probably the best bet. In our case there was a need to keep the server online as long as possible, whilst changes occur every second, even during migration.

So I built a new server and used DRBD to replicate the storage. Once both boxed were synced I only had to switch IPs and disable DRBD.

Deathmage

Does your employer know that moving that much data from virtual to physical is going to take some time. You will run into a destination bottleneck, even if you have 1G vs 10G connections, your south bridge chipset will still be a bottleneck. The transfer could literally no joke take a few days.... I did the same task at a contractor job last year for 12 TB's and it was a 10G network, the RAID 10 array wasn't the problem, the transfer rate of the servers Motherboard was, it took 4 days to transfers, you have 28 TB's.

Then like Jibba says you can't make a calculated assessment that moving it, storage wise, will work correctly.