Port level hardware issues are at Layer 1 of OSI layer, and generally speaking, there is a requirement of some sort of flow (either electrical signals for RJ45, or optical signals for fibre cables) to identify such issues.  The only exception I can think of (based on the cases I have worked on) - is where the ports are lit up on the switch even without anything connected to it. This is usually a backend wiring issue that qualifies the switch for RMA. So if you see anything suspicious going on with the switch, kindly raise a support ticket via https://meraki.cisco.com/support/  and we can assist you accordingly  ... View more

You can set the IP by plugging into the management port and accessing the local status page if you don't have DHCP on the network.   Using the Cisco Meraki Device Local Status Page - Cisco Meraki Documentation ... View more

If you can narrow down the problem to a particular switch or port, there are packet statistics:   This can tell you which ports are seeing the most traffic, and you can also compare sent/received against other switches/ports. ... View more

Yes. ... View more

I would recommend to double check all the configurations as per the document.   There are no specific firewall rules or limitations. If you are polling from outside, please refer here: https://documentation.meraki.com/General_Administration/Monitoring_and_Reporting/SNMP_Overview_and_Configuration#Polling_from_outside_of_the_network   Also, if it still does not work as expected, you can always open up a case with Support and we would be happy to help. 🙂     ... View more

Hello @Jobsp    This could happen if the bottom switch was "Active switch" member. Please find this below document helpful: https://documentation.meraki.com/MS/Stacking/Switch_Stacks#Replacing_a_Stack_Member   " If the Active stack member is replaced there will be a short loss in connectivity when it is powered down while a new Active member is elected".     ... View more