Hyper V over SMB3 live migration

[SMOKEU]

So I'm having a bit of trouble here. I have 2 Windows Server 2012 Hyper V hosts with the VHDs on a Server 2012 file server with an SMB3 share. I've configured the replication between Hyper V host 1 and Hyper V host 2 (from herein referred to as HYPERV1 and HYPERV2, respectively). The replication appears to work fine as stated by the View Replication Health menu. When I right click the VM on HYPERV1 and select Move..., I'm prompted with a Move <hostname> Wizard. Then I select Move the Virtual Machine, then I'm promted to insert the hostname of the 2nd Hyper V host. I then select Move only the virtual machine as I want to leave the storage on the SMB share. Once I click Finish, a small box pops up saying Performing the move. After a few seconds I get an error message saying "There was an error during the move operation" and "The operation failed because a virtual machine with the same identifier already exists. Select a new identifier and try the operation again".

I really need to get this live migration working. I'm a Hyper V n00b and I don't get the choice to use VMWare, so what do I do?

[scracha]

I'm just suprised you're lowering youself by using that evil Microsoft shite you're always spouting about?

[SMOKEU]

I'm just suprised you're lowering youself by using that evil Microsoft shite you're always spouting about?

Well I can't exactly avoid MS all-together since I need to include an AD domain and Hyper-V hosts as per the project requirements. I guess I could have gone with NetApp or FreeNAS instead of SMB, but SMB sounded a bit easier than it turned out to be. So, any constructive ideas?

[p.dath]

I've played with the Hyper-V 2012 replication. I guess I could best some up my experience with it as saying it is not production ready. If you really want to use Hyper-V 2012, then use a SAN and create a Hyper-V windows cluster (which does work reliably).

I've had problems where the replication uses so much system resources it kills the performance of the VM's it is trying to replicate (to the point where they become non-responsive for short periods of time). I've had problems where the replication has stopped working, and nothing indicates this unless you actively go in and check it.

Perhaps in the next release it will be OK.


VMWare Essentials, which gives you licences for up to 6 CPU cores which can be spread across 3 hosts is less than $1000 from memory. Use that, or get a SAN if you want to stick with Hyper-V.

[SMOKEU]

I've played with the Hyper-V 2012 replication. I guess I could best some up my experience with it as saying it is not production ready. If you really want to use Hyper-V 2012, then use a SAN and create a Hyper-V windows cluster (which does work reliably).

I've had problems where the replication uses so much system resources it kills the performance of the VM's it is trying to replicate (to the point where they become non-responsive for short periods of time). I've had problems where the replication has stopped working, and nothing indicates this unless you actively go in and check it.

Perhaps in the next release it will be OK.


VMWare Essentials, which gives you licences for up to 6 CPU cores which can be spread across 3 hosts is less than $1000 from memory. Use that, or get a SAN if you want to stick with Hyper-V.

I should have made it clear earlier that this is only a test environment so it doesn't really matter if it's not up to production spec reliability or performance. Are you suggesting that I try using iSCSI (which is known to be reliable) for this? I've also had problems with the Hyper V replication failing repeatedly, but I got it working with reasonable reliability in the end.

[MOTOXXX]

shared nothing live migration?

Are your hyper V servers the same in terms of physical hardware?

[SMOKEU]

shared nothing live migration?

Are your hyper V servers the same in terms of physical hardware?

It's not shared nothing. The VMs themselves (VHDs etc) are stored on an SMB share on a separate file server. Both Hyper V hosts have a dedicated NIC to that shared storage.

Both Hyper V hosts have identical hardware.

[p.dath]

I should have made it clear earlier that this is only a test environment so it doesn't really matter if it's not up to production spec reliability or performance. Are you suggesting that I try using iSCSI (which is known to be reliable) for this? I've also had problems with the Hyper V replication failing repeatedly, but I got it working with reasonable reliability in the end.

iSCSI will be much more reliable.

[SMOKEU]

iSCSI will be much more reliable.

In hindsight I should have gone with that. I can always change to iSCSI if I want, but I've already started with SMB and will will be nice if I can continue using it. So back to the original problem, it sounds like it doesn't want to do the Live Migration because it thinks the object already exists on the second Hyper V host. It has had a few (aka, many) failed replication attempts due to an unrelated problem which I'm well aware of, but I though that it wouldn't affect the Live Migration. Hyper V over SMB is an MS supported method, so it shouldn't be this much of a cunt to configure.

[Gremlin]

It has had a few (aka, many) failed replication attempts due to an unrelated problem which I'm well aware of, but I though that it wouldn't affect the Live Migration. Hyper V over SMB is an MS supported method, so it shouldn't be this much of a cunt to configure.
Depends what the failures were from. Gotta get a lot of eggs in a row very nicely for things to play nice.

Hah... MS supported, and working in reality are two very different things.

No help on the Hyper V front. We inherited one which never worked very well, thankfully the host blew up (in multiple ways actually), and besides the large amount of work to get back to production, it meant we could move that to VMWare as well...

[SMOKEU]

Depends what the failures were from. Gotta get a lot of eggs in a row very nicely for things to play nice.

Hah... MS supported, and working in reality are two very different things.

No help on the Hyper V front. We inherited one which never worked very well, thankfully the host blew up (in multiple ways actually), and besides the large amount of work to get back to production, it meant we could move that to VMWare as well...

Last night I was introduced to vMotion, and it seems miles ahead of the MS implementation in both functionality and ease of use. I've had a couple of sysadmins with a few years of general experience with Hyper V and VMWare have a look at this project, and it appears that I haven't made any silly mistakes that are immediately obvious to the trained eye.

I checked the event logs and an event about permissions relating to Hyper V appeared, so we decided to disable the firewall on the Hyper V hosts and file server, and give the EVERYONE group full NTFS permissions to the share (yes, I'm well aware of the risks and wouldn't do this in a production environment), but that still didn't fix the problem.

[p.dath]

Last night I was introduced to vMotion, and it seems miles ahead of the MS implementation in both functionality and ease of use. I've had a couple of sysadmins with a few years of general experience with Hyper V and VMWare have a look at this project, and it appears that I haven't made any silly mistakes that are immediately obvious to the trained eye.


It probably isn't you. Replication in Hyper-V is fraught with danger and often breaks.

Migration and Live Migration work, but it my experience, only work reliably work when you are using a SAN with shared storage.

[Akzle]

do it from cli with --log.
Sounds duplicitous. Not sure what it uses as identifier. If its filename then delete(completely) from destination. Or run with a force overwrite switch.

[SMOKEU]

It probably isn't you. Replication in Hyper-V is fraught with danger and often breaks.

Migration and Live Migration work, but it my experience, only work reliably work when you are using a SAN with shared storage.

Sweet, I'll try moving to iSCSI since I know that works if all else fails.


do it from cli with --log.
Sounds duplicitous. Not sure what it uses as identifier. If its filename then delete(completely) from destination. Or run with a force overwrite switch.

Good advice, I'll try doing it with PS.

[SMOKEU]

I got it working! I added a third Hyper-V host to the domain, and did the Live Migration from HyperV1 to HyperV3. I didn't configure replication between the 2, as it seems like it doesn't like doing a Live Migration to a host that has a replica when using SMB, but it works with iSCSI (I stuck with SMB though).

Thanks for your help everyone!

[Akzle]

bro. Install linux.
It fucks samba up liek a motherfucker.

[SMOKEU]

bro. Install linux.
It fucks samba up liek a motherfucker.

I would if I knew how to configure it, but I'd rather stick with MS since I know my way around it much better than I do with Linux.