You can specify a single subnet-level IP mapping rule for a selected configured virtual network mapping on the protected and recovery sites.

Subnet-level mapping eliminates the need to define exact adapter-level IP mapping. Instead, you specify an IP customization rule that Site Recovery Manager applies to relevant adapters. The IP customization rule is used for test and recovery workflows. You cannot reuse IP customization rules between different network mappings.

Important:
  • IP subnet mapping rules support IPv4 only.
  • Rule-based IPv6 customization is not supported in Site Recovery Manager.
  • When you apply IP subnet mapping rules to Windows virtual machines with IPv6 enabled, the IPv6 settings, DHCP or static, remain unaffected after recovery. For Linux virtual machines, IPv6 settings are reset to DHCP.
  • Site Recovery Manager does not evaluate IP mapping rules for virtual machines configured to use manual IP customization.

The IP customization rule applies to virtual machines failing over from a protected site IPv4 subnet to a recovery site IPv4 subnet, for example, from 10.17.23.0/24 to 10.18.22.0/24. The IP customization rule states that during recovery Site Recovery Manager evaluates the existing IP configuration of the recovered virtual machine's NICs and reconfigures static NICs found on the 10.17.23.0/24 subnet for the 10.18.22.0/24 subnet.

If the rule matches, Site Recovery Manager derives the new static IPv4 address from the old one by preserving the host bits of the original IPv4 address and placing it to the target subnet. For example, if the original protected site address is 10.17.23.55/24, the new address is 10.18.22.55/24.

If the default gateway text box is empty, Site Recovery Manager derives the new gateway parameter from the original one by preserving the host bits of the original IPv4 address and placing it in the target subnet. For example, if the original protected site gateway is 10.17.23.1, the new gateway is 10.18.22.1. If you specify an explicit gateway parameter, Site Recovery Manager checks that the IPv4 address syntax is correct and applies it exactly.

Site Recovery Manager applies DNS and other parameters as specified. DHCP-enabled NICs are not subject to customization as their network configuration remains unchanged during recovery.

Procedure

  1. In the vSphere Client, click Site Recovery > Open Site Recovery.
  2. On the Site Recovery home tab, select a site pair and click View Details.
  3. In the left pane click Configure > Network Mappings.
  4. Select a network mapping for which to define a customization rule.
  5. To define a rule, right-click on the mapping and select Add IP Customization Rule.
  6. Specify the subnet IP ranges that map to the protected and recovery sites.
  7. Specify the network settings for the recovery site network.
  8. Click Add to save your changes.