Tips for VM replication to a secondary site

[andreapichler]

Hello
We want use Veeam Backup and Replication v.4 to replicate some VM from a primary site to a secondary site and VMs from the secondary site to the primary (so each site is a backup of the other one).
Our scenario is:
Primary site:
- ESX4 hosts (for example ESX-A,ESX-B) connected to a SAN (via FC)
- Virtual Center server on Phyiscal Hardware with direct connection to the storage (so we can use VCB or VStorage API via SAN)
- VM1,VM2 should be replicated to the secondary site
- VPN connection to the secondary site
Secondary site:
- ESX4 hosts (for example ESX-C,ESX-D) connected to a SAN (via iSCSI)
- Virtual Center server on Phyiscal Hardware with direct connection to the storage (so we can use VCB or VStorage API via SAN)
- VM3,VM4 should be replicated to the primary site
- VPN connection to the primary site
The VM’s to replicate are already v.7.
Veeam will be installed on both sites and each installation connected to both virtual centers.

Here my questions:
- Should I install Veeam Backup & Replication v.4 on the physical Server or in a VM (to use Virtual Appliance Mode) – what do you suggest for performance and mainteniance?
- I create a replication job for VM1 on Veeam installed the primary site using vStorage API in SAN/Virtual Appliance mode (depending on the answer of my first question) and set as target the ESX-C host. I will set maximum compression, enable the changed blocks tracking and set the replica for execution every 10 minutes. I will also set a high number of retries every 10 minutes to avoid a stop of the replication process in case of temporary unavailability of the network, vcenter, remote host, ecc. The first replica will be made on a removable storage. Are these settings ok?
- Can we have replica inconsistencies due to vcenter reboot, host /network unavailability etc.?
- Can I change the target (for example to ESX-D) in the replication job?
- It’s better create one job per VM or one job for all VM’s?
- Other tips/considerations for this enviroment ?


Thanks
Best regards
Andrea

[Vitaliy S.]

Hello Andrea,

1. You can install Veeam Backup and Replication either to a physical box or a Virtual machine. You may try both ways to see what mode suits you best: either SAN with failover or Virtual Appliance mode (in case of VM), please have a look at the following topic that have some speed figures for existing production environments: New Install (Best Setup?).
2. As for the compression level, be aware that you should have a powerful CPU (multi-core) to use best compression (this is only applied to rollbacks though).
3. Regarding your configuration and schedule for the replication jobs, you surely can do the initial replica on the removable storage, so you could run only incrementals over VPN connection, as for 10 minutes interval between each run, it should be achievable with the change block tracking feature, but of course the this as well as the speed values heavily depend on your VPN connection characteristics.
4. In case you have something happened to your vCenter or ESX hosts, the job will not be successfull, but we will be able to repair failed replicas on the next job run.
5. Concerning the change of the destination target, yes we do have this feature available in Veeam Backup and Replication 4.
6. You can either group or use single jobs for your VMs to replicate

Thank you.