Cloud-Native IOS XE Overview

Layer 3 SVI Behavior

Prior to cloud-native IOS XE, Layer3 Meraki switches required at least two IP addresses, one for the management IP and a second for the Layer3 Switch Virtual Interface (SVI). You cannot route traffic through the management-IP, it essentially worked as an out-of-band management interface. In cloud-native IOS XE, the Meraki management interface is now combined with a Layer 3 uplink SVI, using one single IP address, rather than two.

To use Layer3 SVI's with cloud-native IOS XE, the following requirements/conditions apply:

• The management/uplink SVI must be configured for a static IP address. It's highly recommended to configure your management interface to use a static IP address prior to upgrading.
• If you upgrade from Container-based (CS) firmware to Cloud-Native IOS-XE be aware of the following:
  • If you have the management interface on the same VLAN as a configured L3 SVI, the SVI IP address will override the management interface address, and the management interface IP address will be erased. This is done to attempt to preserve L3 routability in the network, but may result in the loss of management traffic such as SNMP or RADIUS when the management IP address changes. For example:
    • Management interface has a static IP of 10.10.10.100 on vlan 10
    • There is also an SVI on VLAN 10 configured for 10.10.10.200.
    • After the upgrade, the switch will use 10.10.10.200.
  • If you have the management interface on a unique VLAN with no overlapping SVI, then the management interface will become a new uplink SVI.
  • If your management IP is configured for DHCP, you be required to assign a static IP address to the uplink SVI before other L3 SVIs can be created. Static addressing is considered a Cisco best practice for Layer 3 switch deployments.

Spanning Tree Changes

Spanning-Tree Protocol (STP) behaves differently in cloud-native IOS XE 17.15.1.

• CS17 and cloud-native IOS XE 17.15.1 exhibit different behaviors in their handling of Spanning Tree Protocol (STP).
• Cloud-native IOS XE runs Multiple Spanning Tree Protocol (MSTP) with PVST simulation enabled and changes the MSTP region identifier to the switch's MAC ID. 

• For spanning-tree root bridges, MSTP is preferred and remains compatible with Rapid-PVST+ as long as VLAN 1 is allowed on the trunk. If VLAN 1 is not configured on the uplink, the downstream Cloud-Native IOS XE/MSTP switch will become the root for all VLANs.

LED Behavior

The system LED on the switch indicates the system status, including the progress of booting and connecting to the Meraki dashboard without logging in into the system or Dashboard. The MS390 switch has a rainbow system LED to indicate the system state. This rainbow LED is not available on Catalyst 9000 hardware. Blue Beacon LED button and the System LED are instead used on Catalyst 9000 hardware to indicate the system status.

• Cloud Native IOS XE firmware continues to use the rainbow LED in the MS390 and Blue Beacon and system LEDs in Catalyst 9000 to provide system status.

  • For the LED behaviour of cloud-managed Catalyst 9000 switches please refer to the table in our documentation on MS390 Series Installation Guide. It stays same in the cloud-native IOS XE firmware.

  • For the LED behaviour of MS390 please refer to our documentation on MS390 Series Installation Guide.However, cloud-native IOS XE with MS390 adds two additional stages (taken from Catalyst 9000), described below: