Questions about hardware compatibility and replication

[corbitech]

Hello,

I have some questions about hardware compatibility and replication. I have not yet deployed Veeam, so I'm trying to gather info for decision-making purposes. I definitely plan to use Veeam for backup purposes, but I also want to explore the possibility of using it for replication as well.

BACKGROUND:

I'm planning to build 2 virtualization servers which will be based on Hyper-V in Windows Server 2016. I do not need (and cannot afford) a 100% automatic fail-over topology. So I'm hoping to build a more budget-friendly topology in which the 1st virtual server will be the "primary" virtual server, and the 2nd virtual server will be used as a "replica" virtual server. My intention is that if the primary virtual server goes down, I can have the replica virtual server take over. The rollover to the replica virtual server does NOT have to be instantaneous. I can afford a brief window of downtime (less than 4 hours).

I plan to have a maximum of 48 virtual machines (25% production and 75% development/test servers), but initially the count will be less than half of that.

QUESTIONS:

1. I understand that both Hyper-V and Veeam support replication. Is Veeam a superior option for virtual machine replication as compared to what's available in Hyper-V? If yes, please list a few examples of what Veeam does better with respect to replication. Also, does Hyper-V offer replication features which are missing in Veeam?

2. As I read through some of the replication requirements of Hyper-V, I found out that both servers should be as similar as possible (especially with respect to CPU). Is this the case with Veeam as well? How forgiving is Veeam with respect to replication when hardware differences exist between primary and replication virtual servers? In my case, the 2 servers will be nearly identical, but they have different CPUs. In my primary virtual server, there are 2X Intel Xeon E5-2650 (V2) 8 core 2.6 GHz CPU. In my replication virtual server, there are 2X Intel Xeon E5-2650 (V1) 8 core 2.0 GHz CPU. So they are basically the same, but the primary virtual server will have a newer generation of CPU. If absolutely necessary, I can upgrade the CPUs in the replication server to match the primary server, but I'd prefer to avoid the expense if possible.

3. If possible, I'd like to have my replication virtual server OFFSITE. I've heard that Hyper-V replication over WAN is not so reliable. Does Veeam support doing replication over WAN? If yes, how well does it work and how efficient is it with respect to bandwidth? I'm planning to have a 50 Mbps connection between my primary site and my replication site. I was hoping to do BOTH offsite backups and replication using Veeam. I'm wondering if this is realistic given my circumstances.

Thanks in advance for any help.

- AK

[Mike Resseler]

Hi Ashok,

I'll try to give you some answers

1. Hyper-V and Veeam replication work differently. Hyper-V works with a journal (so every bit written gets double written in the journal and then forwarded to the other host) while our replication is based on snapshot technology. So the underlying technology is different. You can have large discussions over what is best but I think that Gostev has written it up very nicely (although a few years old, still very valid: microsoft-hyper-v-f25/hyper-v-2012-r2-r ... 16374.html

2. That will not be an issue in your case. The problem around that statement is more with Intel versus AMD as the instruction set is different. So don't worry about that expense

3. We are more efficient compared to Hyper-V, and especially when you would consider our WAN acceleration (see here: https://helpcenter.veeam.com/docs/backu ... tml?ver=95). Another idea here (to save on bandwidth) is to do replication from backup (https://helpcenter.veeam.com/docs/backu ... tml?ver=95)

Hope it helps a bit

Mike

[corbitech]

Thanks, Mike. That helps a lot.

[corbitech]

Mike,

I have a follow-up question regarding your response to #3. You mentioned that it's possible to do replication from a backup. I was not aware of that option. Thanks for suggesting it. But I'd like to clarify one thing.

Let's assume that I have the primary virtual server and the primary Veeam backup server (an installation of all Veeam components on a single physical server with direct attached storage) at Site1. At Site2, I have another Veeam server (which I'll refer to as Veeam offsite server) used for offsite storage of my Veeam backups (using WAN acceleration).

Would it be possible to locate my replica virtual server at Site2 and do replication using the Veeam offsite server? Assume that I would have the flexibility to install whatever Veeam components are needed on the Veeam servers located at Site1 and Site2.

- AK

[Mike Resseler]

Ashok,

I probably misunderstand you here. Are you planning on installing a new Veeam B&R server on site 2? Because what you should do is install a server at site 2 and deploy specific components over there. Things like a repository (to store your offsite backups), WAN accelerator and potentially other components. The main B&R server at the primary site will still do all the commands. (sort of the command and control center, but the actual I/O and other work will be done on the remote parts.)

So you don't need a second installation of B&R, just a second server that hosts certain roles that are needed to receive the backups remotely and do the replication from that backup

Hope it makes sense

Mike

[corbitech]

Mike,

My explanation was poor.

The main purpose of Site2 is to store an offsite backup of all my Veeam backups from Site1. I would install whatever Veeam components are needed at Site2. I don't know exactly which components those are, but it seems that your most recent reply gives me some good ideas there. Assuming that I install the proper components (whatever those happen to be) at Site2, I would also like to use Site2 to replicate virtual machines to a Hyper-V host which also would be located at Site2.

In summary, Site2 would store offsite Veeam backups AND those offsite backups would be used to replicate VMs to a Hyper-V host located at Site2. From your most recent reply, it sounds like this would be possible.

Thanks,

AK

[Mike Resseler]

AK,

That's correct

[Vladimir K]

Hi Mike,
May I return to colleague's question regarding replication between 2 sites?
You've said that the main B&R server should reside on primary site 1, all is needed on the site 2 (DR) is a Windows server with specific Veeam components (repository, WAN accelerator, etc.), but not Veeam B&R Server (command center) itself.
OK. What if primary site went down totally (water flood, fire)? How do I switch to replicas on site 2 if my primary Veeam Server (command center) is totally destroyed? What steps should I take in this case - install Veeam Server on site 2 (I believe I can activate it with the Veeam site 1 license), but the installation process will take some precious time. So is it a good idea to have Veeam Server (command center) on site 2 instead of site 1?
Let's go further - I want to have replicas on site 2 AND "regular" backup on site 1 - in this case, should I have 2 Veeam B&R Servers - on both sites, and have 2 licenses for them?

[DGrinev]

Hi Vladimir and welcome to the community!

It's recommended approach to set up replication jobs on the separate instance of backup server in the DR site. You may have as many backup servers as you need without additional licenses.
This way you will be able to quickly failover VMs in case of a disaster on the production site.

In the scenario with a single backup server, you should use configuration backup and review this topic for additional information.

[Vladimir K]

Hi Dmitry, thanks a lot for the answer!
I've forgot that Veeam licensing is based on the number of CPUs in protected hosts, not on the Veeam servers or other comonents.
One quiestion that I still have is: if we go for 2 Veeam servers scenario (one for the backups on the primary site and one for the replications on the DR site), shall we face the situation with access conflict? Let's assume that one VM is backing up with site 1 Veeam server at the moment. What if Veeam server at site 2 tried to replicate the same VM at the same time? Will backup, replication (or both) jobs fail or just "waiting for backup/replication infrastructure resource availability" message will be logged, and then both jobs finished with no error?
Another approach is to have only one Veeam server that handles backups and replications at DR site, with proxies and repositories for backups at the production site, but I'm afraid in this case there will be a problem with connectivity, as we have a slow WAN link between Site 1 and Site 2 and it will be always filled up with replication data flow. So I think the Veeam Server will be hardly accessable from the VBR console at site 1 with a very slow response.
And the third approach is to wait for the Veeam Availability Orchestrator

[DGrinev]

What if Veeam server at site 2 tried to replicate the same VM at the same time?

During initiation the replication job will send command freeze/unfreeze to the VSS writer in order to prepare the infrastructure for consistent shadow copy creation and that might cause the conflict with the backup job that's already created shadow copy. The result of such conflict might be inconsistent backup or replica.
To avoid such situations you can determine the backup window in scheduler of the replication job to not overlap on the backup job hours.

In case you will manage all the jobs by a single backup server in the DR site, all the conflicts will be resolved by Veeam.
The slow WAN should be ok for managing the jobs that would be processed locally on the production site. Thanks!

[Vladimir K]

Dmitry,
Thank you very much for clarification!

[Gibbs_sa80]

Hi,

I have worked before with Veeam backup, but until today not with Veeam Replication. I have read some of the documentation and watched a couple of video's how to set it up. I'm left with a few questions about the storage and server requirements.
We have 2 Hyper-V clusters in the same network (although separated physically in our second building, but connected with a high speed fiber optic cable). I would like to replicate all VM's (33) to this second cluster that we use as a failover site. We do not use Veeam as backup at this time.
Does Veeam Replication need storage for using only the replication feature, or will Veeam directly replicate to the second cluster and use only the storage available there? Also do I need a second Veeam server on the other cluster? are there any other things I need to consider before setting up Veeam Replication?

Edit: Another question came to mind. Our 2 Hyper-V hosts have 2 sockets, so 4 in total. The other cluster is the same. Do I need a license for 4 or 8 sockets? (the failover site is going to be offline untill needed).

Thanks in advance.

[DGrinev]

Hi and welcome to the community!

You can replicate to the target shared datastore that is available for the cluster.
The recommended approach is to have VBR server at the DR site for the replication jobs.
You don't need licenses for the target hosts.
Please review this thread for additional information. Thanks!

[jonathanbibou]

Hi
Sorry for my English

I have a host (2008 R2) with 3vms HYPER V (also in w2008 R2)
I bought a server (2008 R2) to do replication with veeam 9.5

I have a question :

The job réplication must be create on the source host OR the target host ? i would like create a failover plan if my source host is down.

Thks a lot.

Jonathan

[DGrinev]

Hi Jonathan and welcome to the community!

The recommended approach is to deploy Veeam B&R on the target host and create replication jobs there.
In this case you are able to perform failover even if the source host will be down.
Please read this discussion for additional information. Thanks!

[jonathanbibou]

Hi thks for your respond

Another question please
I have a vm with SAGE L100 with SQL SERVER. I saw différents option like truncate or not. In my managment studio SQL my databases recuperation mode is on "Simple". What is the good option in my job?
Thks a lot.

[DGrinev]

The best practice would be to use application aware processing with the settings mentioned in the User Guide for SQL and Oracle servers.
Please read existing discussions about the Best practices for database backup. Thanks!