sudo iptables -A INPUT -s 10101001 -J ACCEPT

The command you provided adds a rule to the INPUT chain of the iptables firewall. This rule allows incoming traffic from the source IP address 10.10.100.1 to be accepted (allowed) by the firewall. The -A option specifies that the rule is to be appended to the chain, and -J specifies the target action for this rule, which is ACCEPT. The rule will take effect immediately after executing this command.