Hi guys and thanks for your answers.
I have followed these instructions.
https://documentation.meraki.com/MS/Layer_3_Switching/Layer_3_Switch_Example
This is my Transit VLAN
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and on the Switch
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as an example the VLAN 340 on the switch. As DHCP Relay I have chosen the Transit VLAN
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This is my static route on the MX
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and the DHCP server on the MX
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this is my configuration for the switchport
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this way I have created three VLANs on the switch and DHCP servers on the MX.
I am not sure where my mistake is.
I hope I have described everything understandably and you can help me.
Thanks a lot