Have connected my meraki switch ms 120-24p via a trunk link to my WS-C2960X-48TS-L swutch. The meraki still says unreachable.
Find configs f the trunk ports.
have done same on meraki trunk port,ie the native vlan and allowed vlans as well.
If you've connected brand new MS120, configuring via Dashboard won't help.
MS switch's default native VLAN is 1, and it can cause native VLAN mismatch when you connect MS switch into trunk port doesn't use native VLAN 1, thus cannot reach Meraki cloud.
First, you can change Gi1/0/8's native VLAN to 1 and check whether it can reach Dashboard or not.
If it can and have to use native VLAN 10, try to access MS local status page via Management port and change native VLAN to 10.
Plus, if you're not using DHCP, you need to configure switch's uplink IP, too.