@Snika connect your WAN to the green port below and your LAN to the port with the green dot:
In the future if you need a 10Gb connection then you can use ports 19-26 on the MX250.
Remember both WAN1 and WAN2 on the MX250 are SFP+ ports so if you have a cable with an RJ-45 on it, you will need a transceiver such as the Cisco GLC-T (1Gbps) or similar.
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