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   nping    ( 1 )

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ARP MODE

--arp-type type (ICMP Type) This option specifies which type of ARP messages should be generated. type can be supplied in two different ways. You can use the official numbers assigned by IANA[2] (e.g. --arp-type 1 for ARP Request), or you can use one of the mnemonics from the section called 'ARP Types'.

--arp-sender-mac mac (Sender MAC address) This option sets the Sender Hardware Address field of the ARP header. Although ARP supports many types of link layer addresses, currently Nping only supports MAC addresses. mac must be specified using the traditional MAC notation (e.g. 00:0a:8a:32:f4:ae). You can also use hyphens as separators (e.g. 00-0a-8a-32-f4-ae).

--arp-sender-ip addr (Sender IP address) This option sets the Sender IP field of the ARP header. addr can be given as an IPv4 address or a hostname.

--arp-target-mac mac (target MAC address) This option sets the Target Hardware Address field of the ARP header.

--arp-target-ip addr (target ip address) This option sets the Target IP field of the ARP header.

ARP Types These identifiers may be used as mnemonics for the ARP type numbers given to the --arp-type option.

arp-request, arp, a ARP Request (type 1). ARP requests are used to translate network layer addresses (normally IP addresses) to link layer addresses (usually MAC addresses). Basically, and ARP request is a broadcasted message that asks the host in the same network segment that has a given IP address to provide its MAC address.

arp-reply, arp-rep, ar ARP Reply (type 2). An ARP reply is a message that a host sends in response to an ARP request to provide its link layer address.

rarp-request, rarp, r RARP Requests (type 3). RARP requests are used to translate a link layer address (normally a MAC address) to a network layer address (usually an IP address). Basically a RARP request is a broadcasted message sent by a host that wants to know his own IP address because it doesn't have any. It was the first protocol designed to solve the bootstrapping problem. However, RARP is now obsolete and DHCP is used instead. For more information about RARP see RFC 903.

rarp-reply, rarp-rep, rr RARP Reply (type 4). A RARP reply is a message sent in response to a RARP request to provide an IP address to the host that sent the RARP request in the first place.

drarp-request, drarp, d Dynamic RARP Request (type 5). Dynamic RARP is an extension to RARP used to obtain or assign a network layer address from a fixed link layer address. DRARP was used mainly in Sun Microsystems platforms in the late 90's but now it's no longer used. See RFC 1931 for more information.

drarp-reply, drarp-rep, dr Dynamic RARP Reply (type 6). A DRARP reply is a message sent in response to a RARP request to provide network layer address.

drarp-error, drarp-err, de DRARP Error (type 7). DRARP Error messages are usually sent in response to DRARP requests to inform of some error. In DRARP Error messages, the Target Protocol Address field is used to carry an error code (usually in the first byte). The error code is intended to tell why no target protocol address is being returned. For more information see RFC 1931.

inarp-request, inarp, i Inverse ARP Request (type 8). InARP requests are used to translate a link layer address to a network layer address. It is similar to RARP request but in this case, the sender of the InARP request wants to know the network layer address of another node, not its own address. InARP is mainly used in Frame Relay and ATM networks. For more information see RFC 2390.

inarp-reply, inarp-rep, ir Inverse ARP Reply (type 9). InARP reply messages are sent in response to InARP requests to provide the network layer address associated with the host that has a given link layer address.

arp-nak, an ARP NAK (type 10). ARP NAK messages are an extension to the ATMARP protocol and they are used to improve the robustness of the ATMARP server mechanism. With ARP NAK, a client can determine the difference between a catastrophic server failure and an ATMARP table lookup failure. See RFC 1577 for more information.