Issue with Meraki MX 105 Configuration

[lc-gabriellima]

Hello everyone,

I’m encountering an issue with my Meraki MX 105. I connected an Ethernet cable to the WAN port, as per the setup guide, to connect to the cloud and complete the claiming process. However, the device is not obtaining an IP address.

Should I connect it to a LAN or WAN port? Also, I understand that I might need to request firewall rules for cloud access, but it isn’t even picking up an IP address. Could you please assist me?

[alemabrahao]

So that it can communicate with the Meraki Cloud over the WAN. The question is, does your ISP provide the address via DHCP? Generally, as far as I know, it is not possible and it is necessary to configure the static IP.

https://documentation.meraki.com/MX/MX_Installation_Guides/MX95%2F%2FMX105_Series_Hardware_Installat...

[lc-gabriellima]

Hello,

Thank you for the information! What I was trying to do is connect my Meraki to the cloud by using one of the LAN ports on my MX to obtain an IP from the internal network. The idea was to use this IP to establish a connection to the Meraki cloud.

If you could guide me on the best way to configure this, I would greatly appreciate it!

Best regards,

[alemabrahao]

You need to configure the WAN port. The link I sent previously has information on how to do the installation.

Here is another link to the quick setup.

https://documentation.meraki.com/MX/MX_Quick_Start

[PhilipDAth]

You can plug the WAN port into your internal network to allow the MX to connect to the cloud.

[Boomerang94]

Greetings,

When we connect the WAN cable of the MX to another device (ISP modem etc.) - by default it sends DHCP Discover messages to try to obtain an IP address. If the upstream device is running as a DHCP server, the MX gets an IP address (by completing DHCP DORA process) and then tries to go to Internet + Meraki dashboard via that gateway. However, there are many instances where the ISP modem might not be running as a DHCP server and requires the customers to manually configure a static IP address. So the first test is to understand, whether the upstream device is running as a DHCP server or not. As a quick test, instead of using MX105 WAN interface, you can connect that upstream device to your laptop to check if the laptop gets an IP address or not. 

For the MX part, the local status page will give you the best information here. In the "Ethernet" section - you will see one of two scenarios:

- "This security appliance is connected to a local network" - this means your MX has an IP and gateway is working fine 
- "The security appliance is trying to join a network or find a working ethernet connection" - this means your MX does not have a working IP or the gateway IP is not responding to our ARP requests 

As per your second comment, if you are trying to connect this MX105 as a LAN client on another MX device, please make sure that the port you are connecting to is using correct native VLANs and not dropping untagged messages (as DHCP messages from MX105 WAN will be untagged).

To drill down even further, you can also run pcap on MX LAN interface to check the DHCP exchange between the existing MX and MX105 WAN. This way you can see exactly on which step the DHCP is failing. 

If the issue still persists, please reach out to Cisco Meraki support via https://meraki.cisco.com/support/ and one of our engineers can check this for you.