Upgrade MX 84 to 16.16. Switch stack loosing connectivity

[Banfield75]

Hi

Our MX84 in HA mode where upgraded to 16.16 a couple weeks ago. Since then there is now and then a brief period loos of connectivity with underlaying switch stacked par. The switch HA connected as fully redundant switch stack. I have tested ping from a computer. During outage there is ping lost, the period is less then 1 min. So it´s no reboot of the switch.

[cmr]

We have several pairs of MX84s running 16.16 and don't have a similar issue.  Is it the switches on the LAN side that are losing connection?  What make and model are they and how many connections are them from each MX on the LAN ports?

[Banfield75]

It´s MS210-24 port and 48 port stacked that is stacked. Each switch is connected  to each MX84 as it should be in fully redundant switch stack. MX Warm Spare - High-Availability Pair - Cisco Meraki

[cmr]

@Banfield75 try disconnecting one cable from each MX to the switch stack, that may regain reliability.

[Banfield75]

I have tried that. I must say that support sucks. 

This time and previously you stuck in a call que of 45 min.

You can´t work with one and same engineer. You need to call again.

The only suggestion I always get it.... upgrade to latest version.... Even if it´s beta.

I have now upgraded to 16.16.1 and will upgrade to 17.6

[Banfield75]

I forgott to mention that one SFP is connected to one of the switches in the stack. 

[VictorJohnsonan]

At the moment I have the MX connected to a Cisco Catalyst stack that contains 3 VLANS

I have an SVI between the MX and Cisco catalyst switch

MX IP 10.10.10.1 

Cisco catalyst Stack IP 10.10.10.254 

Then on the MX I have routes configured to the VLANs on the Cisco catalyst VLANS

eg subnet 192.168.1.0/24  Gateway ip 10.10.10.254 

I also have routes on the Cisco catalyst Stack that point back to the Meraki VPN LAN that I have configured..

I need to remove the Cisco catalyst Stack and replace with the Meraki MS stack and was expecting to configure it in the same way. Set an IP for the MS stack and set up new static routes on the MX to point to this. Clearly I need to do this a different way?

[cmr]

@VictorJohnsonan is is almost exactly the same, the only difference being that you would have a 4th VLAN for the switch management interfaces that would not have an SVI, with the gateway pointing at the interface on the MX.

i.e. MX IP on VLAN4 10.10.4.1, switch management interfaces set to VLAN4 with the default gateway set to 10.10.4.1.

We do this by running DHCP on the MX as the switch management interfaces don't need to be static unless you have need an old SIEM solution that relies on an IP address for source identification.

[Banfield75]

Downgraded to 15.44. Everything works as before. Been waiting for 1.5h in call que so that Meraki support can uppgrade to 17.6.