Can the e0M and SP/BMC interfaces be configured on different subnets?
Applies to
- All FAS systems
- All AFF systems (except AFF A700s and AFF A800)
Answer
Short answer is yes, but they shouldn't be. Although there are no guardrails to prevent that misconfiguration, the e0M and SP/BMC should always be in the same subnet.
Logical interfaces (LIFs) configured on the e0M interface, and the SP/BMC network interface, both connect to the external management network by means of an internal network switch to a single physical port (graphically identified as the "wrench" port).
- IP addresses for both interfaces must be on the same subnet directly reachable via the wrench port
- Isolate management network traffic
Note1: Controllers that have separate, dedicated RJ45 ports for the e0M and BMC interfaces - such as the AFF A700s and the AFF A800 - can been configured on different subnets.
Note2: Regardless of whether the controller has shared or separate e0M and SP/BMC interfaces, best-practice is that neither interface should be configured within any data subnet. Excessive data traffic can pre-empt or otherwise interfere with access to the e0M or SP/BMC interface, impairing overall management of the controller.
Additional Information
The e0M interface is dedicated to ONTAP management activities, whereas the SP/BMC interface is dedicated to out-of-band ancilliary functions (remote power on/off/status, log collection, etc.). Neither interface should be within any data subnet.
- The e0M management interface and the SP/BMC network interface are connected to two ports of the controller's internal switch.
- A third port of the internal switch is connected to the external
Wrench
port (RJ45) which allows access from outside.
Note: The e0M and SP/BMC interfaces do not support VLAN tagging and must be connected to an access port. See e0M, Service Processor or BMC unreachable on network due to VLAN tagging on switch port