XML -h [icmp] Print a brief help message. (Apache web server)
XML -h [icmp] Print a brief help message. If the option icmp is given, print a list of valid ICMP types. Targets A target may be the name of a chain or one of the following special values. ACCEPT Let the packet through. DROP Drop the packet. QUEUE Send packets to the user space for processing. RETURN Stop traversing the current chain and return to the point in the previous chain from which this one was called. If RETURN is the target of a rule in a built-in chain, the built-in chain’s default policy is applied. Rule specification parameters These options are used to create rules for use with the preceding commands. Rules consist of some matching criteria and usually a target to jump to (-j) if the match is made. Many of the parameters for these matching rules can be expressed as a negative with an exclamation point (!) meaning “not.” Those rules will match everything except the given parameter. -p [!] name, –protocol [!]$PARAMETER Match packets of protocol name. The value of name can be given as a name or number as found in the file /etc/protocols. The most common values are tcp, udp, icmp, or the special value all. The number 0 is equivalent to all and this is the default value when this option is not used. If there are extended matching rules associated with the specified protocol, they will be loaded automatically. You need not use the -m option to load them. -s [!] address[/mask] [!] [port], –source [!] address[/mask] [!] [port] Match packets with the source address. The address may be supplied as a hostname, a network name, or an IP address. The optional mask is the netmask to use and may be supplied either in the traditional form (e.g., /255.255.255.0) or in the modern form (e.g., /24). -d [!] address[/mask] [!] [port], –destination [!] address[/mask] [port] Match packets from the destination address. See the description of -s for the syntax of this option. -j target, –jump target Jump to a special target or a user-defined chain. If this option is not