iptables: update page; ip6tables, ip{6,}tables-{restore,save}: add page (#10715)

* iptables: update page

* iptables-{restore,save}: add page

* ip6tables, ip6tables-{restore,save}: add alias page

* iptables-save: remove trailing whitespace

pages/linux/ip6tables-restore.md

@@ -0,0 +1,7 @@
+# ip6tables-restore
+
+> This command is an alias of `iptables-restore` for the IPv6 firewall.
+
+- View documentation for the original command:
+
+`tldr iptables-restore`

pages/linux/ip6tables-save.md

@@ -0,0 +1,7 @@
+# ip6tables-save
+
+> This command is an alias of `iptables-save` for the IPv6 firewall.
+
+- View documentation for the original command:
+
+`tldr iptables-save`

pages/linux/ip6tables.md

@@ -0,0 +1,7 @@
+# ip6tables
+
+> This command is an alias of `iptables` for the IPv6 firewall.
+
+- View documentation for the original command:
+
+`tldr iptables`

pages/linux/iptables-restore.md

@@ -0,0 +1,9 @@
+# iptables-restore
+
+> Restore the `iptables` IPv4 configuration.
+> Use `ip6tables-restore` to do the same for IPv6.
+> More information: <https://manned.org/iptables-restore>.
+
+- Restore the `iptables` configuration from a file:
+
+`sudo iptables-restore {{path/to/file}}`

pages/linux/iptables-save.md

@@ -0,0 +1,17 @@
+# iptables-save
+
+> Save the `iptables` IPv4 configuration.
+> Use `ip6tables-save` to to the same for IPv6.
+> More information: <https://manned.org/iptables-save>.
+
+- Print the `iptables` configuration:
+
+`sudo iptables-save`
+
+- Print the `iptables` configuration of a specific [t]able:
+
+`sudo iptables-save --table {{table}}`
+
+- Save the `iptables` configuration to a [f]ile:
+
+`sudo iptables-save --file {{path/to/file}}`

pages/linux/iptables.md

@@ -1,7 +1,8 @@
 # iptables
 
-> Program that allows configuration of tables, chains and rules provided by the Linux kernel firewall.
-> More information: <https://www.netfilter.org/projects/iptables/>.
+> Configure tables, chains and rules of the Linux kernel IPv4 firewall.
+> Use `ip6tables` to set rules for IPv6 traffic. See also: `iptables-save`, `iptables-restore`.
+> More information: <https://manned.org/iptables>.
 
 - View chains, rules, packet/byte counters and line numbers for the filter table:
 
@@ -17,7 +18,7 @@
 
 - [A]ppend rule to chain policy for IP considering [p]rotocol and port:
 
-`sudo iptables --append {{chain}} --source {{ip}} --protocol {{protocol}} --dport {{port}} --jump {{rule}}`
+`sudo iptables --append {{chain}} --source {{ip}} --protocol {{tcp|udp|icmp|...}} --dport {{port}} --jump {{rule}}`
 
 - Add a NAT rule to translate all traffic from the `192.168.0.0/24` subnet to the host's public IP:
 
@@ -26,11 +27,3 @@
 - [D]elete chain rule:
 
 `sudo iptables --delete {{chain}} {{rule_line_number}}`
-
-- Save `iptables` configuration of a given [t]able to a file:
-
-`sudo iptables-save --table {{tablename}} > {{path/to/iptables_file}}`
-
-- Restore `iptables` configuration from a file:
-
-`sudo iptables-restore < {{path/to/iptables_file}}`