Uruchomienie, wykonanie: iptables command [options]
Jak działa IPTABLES, co robi IPTABLES: System administration command. Configure netfilter
There are three built-in tables for iptables: one for network filtering (filter), one for Network Address Translation (nat), and the last for specialized packet alterations (mangle). Firewall rules are organized into chains, ordered checklists of rules that the kernel works through looking for matches. The filter table has three built-in chains: INPUT, OUTPUT, and FORWARD. The INPUT and OUTPUT chains handle packets originating from or destined for the host system. The FORWARD chain handles packets just passing through the host system. The nat table also has three built-in chains: PREROUTING, POSTROUTING, and OUTPUT. mangle has only two chains: PREROUTING and OUTPUT.
netfilter checks packets entering the system. After applying any PREROUTING rules, it passes them to the INPUT chain, or to the FORWARD chain if the packet is just passing through. Upon leaving, the system packets are passed to the OUTPUT chain and then on to any POSTROUTING rules. Each of these chains has a default target (a policy) in case no match is found. User-defined chains can also be created and used as targets for packets but do not have default policies. If no match can be found in a user-defined chain, the packet is returned to the chain from which it was called and tested against the next rule in that chain.
iptables changes only the rules in the running kernel. When the system is powered off, all changes are lost. You can use the iptables-save command to make a script you can run with iptables-restore to restore your firewall settings. Such a script is often called at bootup. Many distributions have an iptables initialization script that uses the output from iptables-save
Dostępne opcje, wywołanie IPTABLES: Print help message. If icmp is specified, a list of valid ICMP type names will be printed. -h can also be used with the -m option to get help on an extension module. Used with the -L command. Add the line number to the beginning of each rule in a listing, indicating its position in the chain. Explicitly load matching rule extensions associated with module. See the next section. Use specified command to load any necessary kernel modules while adding or inserting rules into a chain. Print all IP address and port numbers in numeric form. By default, text names are displayed when possible. Apply rules to the specified table. Rules apply to the filter table by default. Verbose mode. Expand all numbers in a listing (-L). Display the exact value of the packet and byte counters instead of rounded figures.
- Co znaczy :
- Porównanie display the contents of the ISO9660 image isoimage . Used to verify the integrity of the directory inside the image. isodump displays the first portion of the root directory and waits for commands co znaczy.
- Krzyżówka :
- Dlaczego reader. Display online documentation previously built from Texinfo input. Info files are arranged in a hierarchy and can contain menus for subtopics. When entered without options, the command krzyżówka.
- Co to jest :
- Jak lepiej administration command. Print the IP firewall rules currently stored in the kernel to stdout. Output may be redirected to a file that can later be used by iptables-restore to restore the firewall co to jest.
- Słownik :
- Kiedy System administration command. Initialize system. Usually run from the boot loader—e.g., lilo or grub słownik.
- Czym jest :
- Od czego zależy administration command. Print report on interprocess communication (IPC) message queues, shared memory segments, and semaphore arrays for which the current process has read access. Options can be czym jest.
Użycie IPTABLES zastosowanie komendy na linii poleceńw Słownik I .
