TLDR
Enter a command. For example: pidstat, kpartx, gcov, mkswap, dumpe2fs.

iptables

 
Program that allows configuration of tables, chains and rules provided by the Linux kernel firewall. More information: https://www.netfilter.org/projects/iptables/.
 
  • View chains, rules, and packet/byte counters for the filter table:
     
    sudo iptables -vnL
     
  • Set chain policy rule:
     
    sudo iptables -P {{chain}} {{rule}}
     
  • Append rule to chain policy for IP:
     
    sudo iptables -A {{chain}} -s {{ip}} -j {{rule}}
     
  • Append rule to chain policy for IP considering protocol and port:
     
    sudo iptables -A {{chain}} -s {{ip}} -p {{protocol}} --dport {{port}} -j {{rule}}
     
  • Add a NAT rule to translate all traffic from the 192.168.0.0/24 subnet to the host's public IP:
     
    sudo iptables -t {{nat}} -A {{POSTROUTING}} -s {{192.168.0.0/24}} -j {{MASQUERADE}}
     
  • Delete chain rule:
     
    sudo iptables -D {{chain}} {{rule_line_number}}
     
  • Save iptables configuration of a given table to a file:
     
    sudo iptables-save -t {{tablename}} > {{path/to/iptables_file}}
     
  • Restore iptables configuration from a file:
     
    sudo iptables-restore < {{path/to/iptables_file}}

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