Final answer:
The first step to take when encountering a virus attack on a local network is to disconnect the internet by unplugging all Ethernet cables.
Step-by-step explanation:
If you discover a virus attack on your local network, the first step you should take is to disconnect the internet by unplugging all Ethernet cables. This will prevent the virus from spreading further and potentially infecting other devices on the network. After disconnecting the internet, you can then proceed to other necessary steps like notifying department heads and unplugging all servers and UPS battery backups, if needed.
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