I am working on DR site configuration.
Connection between our production and DR site is through site to site VPN. So they are on 2 different subnets.
I am using Veeam and replication jobs to backup VMs from production to the DR site.
Replication works just fine, but I am trying to figure out how to resolve DNS and network mapping.
When configuring Replication job, there are 2 options, Network Mapping and Re-IP. What is difference between those 2? As far as I can understand, they kind of do the same job. If my VM has 10.0.5.25 address on production side, it will have 192.168.0.25 on the DR site. Do I need both of those options enabled or I can use only one of them?
Below is explanation from Veeam Help center about Network Mapping and Re-IP Rules:
By default, a replicated VM uses the same network configuration as the original VM. If the network in the DR site does not match the production network, you can create a network mapping table for the replication job. The table maps source networks to target networks.
During every job run, Veeam Backup & Replication checks the network configuration of the original VM against the mapping table. If the original VM network matches a source network in the table, Veeam Backup & Replication updates the replica configuration file to replace the source network with the target one. The VM replica is then re-registered (for legacy VM replicas, not snapshot VM replicas). Thus, network settings of a VM replica are always kept up to date with the DR site requirements. In case you choose to fail over to the VM replica, it will be connected to the correct network.
For Microsoft VMs, Veeam Backup & Replication also automates reconfiguration of VM IP addresses. If the IP addressing scheme in the production site differs from the DR site scheme, you can create a number of Re IP rules for the replication job.
When you fail over to the replica, Veeam Backup & Replication checks if any of the specified Re-IP rules apply to the replica. If a rule applies, Veeam Backup & Replication mounts VM disks of the replica to the backup server and changes its IP address configuration via the Microsoft Windows registry. The whole operation takes less than a second. If failover is undone for any reason or if you fail back to the original location, replica IP address is changed back to the pre-failover state.