Standalone MS210 to stack

[MassimoB]

I need to add a second switch to an existing standalone MS210 and convert it to stack, is it safe to follow the meraki documentation being sure to have any issue?

What happens to the configuration on the existing switch?

I'm asking this because I have management interface on existing switch configured on a vlan which reach the internet trough a port channel in trunk mode only, if I loose port channel configuration i have no way to access not only the switch but also the upstream firewall.  

[Ryan_Miles]

The existing switch will be fine. Creating a stack doesn't impact the current config. Note the second switch will require a mgmt IP just like the first switch has today.

[MassimoB]

Thanks Ryan, that's what I suppose it should be, but I in my only previous experience on moving from standalone to stack I did loose port channels on the standalone switch, since in this case management interface is reching the internet through a port channel I'm worried about losing switch management and having to struggle with a local engineer (the site is in Australia and I'm in Europe) to change management locally.

I'd like to setup an emergency plan which can easily recover from management interface loss, do you have any idea?

Which is the switch behaviour when management interface cannot reach meraki cloud?

The switch has different L3 interfaces and a dedicated management on a non standard vlan (not vlan 1), all of them are connected to the firewalls through the same port channells.  

[JacekJ · Accepted solution]

There is quite a few ways you can do this.

But I would go with configuring the new switch as a stand-alone one, boot it up, let it upgrade.

Then you can connect the stacking cables and remove the redundant internet connection.

The dashboard will show you that you have switches that are physically stacked in the stacking section and you just apply that.

I don't think you will loose any configs, this never happened to me before - was your experience with Meraki switches?

If you come from classic Cisco stacks - bear in mind that the Merakis don't share one management IP, they will keep their separate ones.

Also, if they loose contact with the internet, the device will try to find its way across different vlans (I suppose they look what they see in the traffic) and set their IP via DHCP to regain dashboard connectivity.

[MassimoB]

Yes it was the same scenario, MS210 standalone to stack and quite the same configuration as the one I need to stack now, but most probably I did some mistake.

Nice to know the switch will try to use production vlans in case it loses access to the cloud with management vlan, thanks a lot.

Last thing, Meraki suggests to use a dedicated vlan for management, which is the exact reason for that seggestion and what happens if I do not comply with that?

[JacekJ]

This is weird then, I didn't use MS210, I have MS225 in production and a few others, but never had this one happening.

You could always set up one port in a classic way instead of aggregating them, then you should be 100% sure that there will be nothing happening.

Also, if you lost the config, didn't the ports revert to trunk with native vlan 1 as the default setting? Wouldn't that keep your setup running? Meraki switches detect if there is LACP running on the other side and enable that if needed automatically.

The dedicated vlan for management is best practice, to separate the management traffic from other production stuff, security reasons and many more.