Digi LR54 User Manual page 882

Firewall
Repeat to add a new rule. Up to 30 rules can be configured.
10. Click Apply to save the configuration and apply the change.
LR54 User Guide
IPv4 address: Only traffic destined for the IP address typed in IPv4 address
n
will be matched. Use the format IPv4_address[/netmask], or use any to match
any IPv4 address.
IPv6 address: Only traffic destined for the IP address typed in IPv6 address
n
will be matched. Use the format IPv6_address[/prefix_length], or use any to
match any IPv6 address.
Configure Quality of Service options
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