Hi @TimRobberechts ,
This is right, The Cisco Meraki MS225 series switches do not support 40G QSFP+ transceivers, including the MA-QSFP-40G-SR4. The MS225 series switches are designed to support 1G and 10G SFP/SFP+ transceivers.
For 40G connectivity, you would need to look at other Cisco Meraki switch models that support QSFP+ ports, such as the MS425, MS390 and other models mentioned in this article.
BR
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