@wizard_123 I don't think you can. The MS450 has only QSFP+ and QSFP28 ports. On other Meraki switches that have QSFP+ ports (MS355), you cannot use the QSFP+ to SFP+ convertor available from FS.com. the datasheet for the MS450 appears to be wrong, as it suggests that the bulk of the ports on the MS450 can connect at 10Gbps...
I don't have any MS450 switches, so they might behave differently to the MS355, but I'd be surprised.
Can you install a QSFP+ module in the Fortigate?
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