The following sections of this chapter provide recommendations and considerations for designing business continuity and DR solutions for converged systems.
Two FC-WAN configurations are supported on converged systems:
- External FC-WAN
- Internal FC-WAN (the most commonly used configuration)
Table 79. FC-WAN configurations on converged systems
FC switches with FC-WAN replication are in place. VPLEX WAN-COM replication ports connect directly to external switches, and no ISLs exist between the converged systems.
The customer has one of the following:
- An existing point-to-point dark fiber link, which can be terminated into the converged system FC.
- DWDM multiplexor (MUX), which can be connected with an ISL to the converged system FC switch.
Use the correct SFPs. A standard shortwave SFP has a limit of 300 meters (approximately 984 ft). If the connection is greater than 300 meters, use longwave SFPs.
When you deploy VPLEX Metro with internal FC-WAN connectivity, ensure that you:
- Keep VSAN 10 and 11 local and isolated to a single Cisco MDS switch. Additional VSANs are required to facilitate VPLEX FC-WAN replication traffic.
- Configure VSAN 30 for Fabric A and VSAN 31 for Fabric B as follows:
- Dedicate VSAN 30 and 31 to FC-WAN replication traffic.
- Extend VSAN 30 between both Fabric A switches.
- Extend VSAN 31 between both Fabric B switches.
- Configure VSAN 30 and 31 with unique FC domain Identifiers between converged systems. Use even numbers for Fabric A and odd numbers for Fabric B.
- To avoid a configuration mismatch when attempting to extend (merge) VSANs, do not complete any zoning activities until after the required VSAN has extended successfully.
Any new switch can become the principal switch when it joins a stable fabric. During the principal switch selection phase, the switch with the highest priority becomes the principal switch.
- Ensure that you:
- Configure VSAN 30 and 31 with a higher switch priority on the primary converged system to enforce wanted roles.
By default, the configured priority is 128 and the valid range is 1 to 254.
- Do not use a switch priority value of 1. This is necessary to allow for future migration scenarios.
If two switches have the same priority, the switch with the lower WWN becomes the principal switch.
- If you extend VSANs between new and existing Cisco MDS switches or unified Cisco Nexus switches, verify that the merge conditions, such as zoning mode and zoneset distribution, are correct. These switches can have different default configurations.