Solution
A MAC Address check must be configured from the CLI with the commands below.
config vpn ssl web portal
edit <portal_name>
set tunnel-mode enable
set mac-addr-check enable
config mac-addr-check-rule
edit <rule_name>
set mac-addr-list <address> [address]
set mac-addr-mask <mask between 1-48>
next
end
set mac-addr-action {allow | deny}
next
end
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