How to Calculate MX WAN MAC Addresses
Overview
Cisco Meraki MX and Z-Series Security devices carry a physical label with a base MAC address that may differ from the observed MAC address of the actual interface. Obtaining the actual MAC address of an interface normally requires a packet capture.
To save time, you can calculate the MAC address of currently supported MX and Z-Series devices instead. This article explains how to locate the base MAC address, calculate a WAN interface MAC address from it, and apply the correct per-model offset.
A MAC address is a unique hardware address that identifies a device. You can find Cisco Meraki MAC addresses using three methods: physical inspection, the dashboard device page, and the device's local status page.
Prerequisites
- A Cisco Meraki device (for example, an MR, MS, or MX).
- Access to the Cisco Meraki dashboard with appropriate permissions to view the device, if you plan to use the Dashboard method.
- Network access to the device's local status page, if you plan to use that method.
Step-by-step instructions
Locate the base MAC address
Use any of the following three methods to locate the MAC address of a Cisco Meraki device.
Physically inspect the device
Locate the device information sticker on the device to find the MAC address. The following image shows the information sticker on an MR16 access point:
Use the dashboard device page
If the device has successfully checked into dashboard, find the MAC address on its dashboard device page. The following image shows the MAC address on an MR33 access point listed in dashboard:
Use the device local status page
Access the device's local status page to find the MAC address. Refer to Local Status Page documentation for more information on accessing the local status page.
Calculate the WAN interface MAC address
Calculate MAC addresses for Cisco Meraki MX and Z-Series devices by taking the last digit of the MAC address, represented as "X" in the offset table, and adding the offset noted for the device. Count in hexadecimal.
For example, calculate the MAC for the WAN 1 interface of an MX64 from the base MAC address AA:BB:CC:06:25:E8:
-
Check the offset table. The MX64 uses a plus 5 hexadecimal offset for WAN 1.
-
Add the offset to the last digit, counting in hexadecimal: 0xE8 + 5 = 0xED.
-
The resulting WAN 1 MAC address is AA:BB:CC:06:25:ED.
Cisco Meraki MX and Z-Series Security devices operating in passthrough mode use the base MAC address for their WAN interface.
The MX75/85/95/105 support a third WAN (backup uplink) starting in MX 18.208 firmware. Refer to the MultiWAN Backup Uplink document for details.
Offset table
The following list shows the MAC offset of the interfaces for currently supported MX and Z-Series devices.
MX
|
Model |
WAN 1 Offset |
WAN 2 Offset |
WAN 3 Offset |
|
MX60 |
X+5 |
X+4 |
N/A |
|
MX60W |
X+5 |
X+4 |
N/A |
|
MX64 |
X+5 |
X+4 |
N/A |
|
MX64W |
X+5 |
X+4 |
N/A |
|
MX65 |
X+1 |
X+2 |
N/A |
|
MX65W |
X+1 |
X+2 |
N/A |
|
MX67 |
X+1 |
X+2 |
N/A |
|
MX67W |
X+1 |
X+2 |
N/A |
|
MX67C |
X+1 |
X+2 |
N/A |
|
MX68 |
X+1 |
X+2 |
N/A |
|
MX68W |
X+1 |
X+2 |
N/A |
|
MX68CW |
X+1 |
X+2 |
N/A |
| MX75 | X+1 | X+2 | X+3 |
|
MX80 |
X+1 |
X+2 |
N/A |
|
MX84 |
X+1 |
X+2 |
N/A |
| MX85 | X+1 | X+2 | X+4 |
|
MX90 |
X+1 |
X+2 |
N/A |
| MX95 | X+1 | X+2 | X+4 |
|
MX100 |
X+1 |
X+2 |
N/A |
| MX105 | X+1 | X+2 | X+4 |
|
MX250 |
X+1 |
X+2 |
N/A |
|
MX400 |
X+2 |
X+4 |
N/A |
|
MX450 |
X+1 |
X+2 |
N/A |
|
MX600 |
X+2 |
X+4 |
N/A |
Z-Series
|
Models |
Offset |
|
Z1 |
X+5 |
|
Z3/C |
X+1 |
|
Z4/C |
X+1 |
Verification
Confirm the calculated MAC address by comparing it against the actual interface MAC address observed in a packet capture from the relevant WAN interface. A match confirms the calculation is correct.
Troubleshooting
Meraki WAN appliances and switches configured in warm spare also use virtual MAC addresses. The MAC address shown by the methods above may differ from the virtual MAC used by the HA (High availability) pair.
- For more information on virtual MAC addresses for HA pair WAN appliances, refer to the Virtual MAC Addresses documentation.
- For more information on virtual MAC addresses for switches in warm spare, refer to the How Warm Spare Works documentation.