Implementation of Address Resolution Protocol.
Syntax:
arp view [IP]
arp add IP MAC|auto proxy
arp del IP|all [proxy]
arp [-]freeze
arp [-]proxyall [$ACL]
ARP protocol serves for IP to MAC-address mapping and vice versa. For example in Ethernet it allows to transform IP destination address into its 48-bit Ethernet address for packet forwarding over LAN.
In common case ARP works automatically making address resolution as it is necessary. But there are some cases when ARP tables should be corrected manually and arp command solves this problem.
The command has several forms:
arp view [IP]
Displays ARP records for IP -address. Displays all ARP records if address is not specified:
arp add IP MAC [proxy] arp add IP auto proxy
Adds record into the ARP table. MAC -address mapped to IP -address. If keyword proxy specified then the system will announce this information as response to the requests from other stations, acting as proxy ARP server, even if this IP -address is not system own address. In this case instead of MAC-address one may specify auto keyword.
arp del IP | all [proxy]
Deletes the record for IP . Or all records in the system if keyword all specified. If optional parameter proxy specified, then only proxy IP -addresses will be deleted.
arp [-]freeze
Enables to freeze ARP table. No more automatically updates allowed. The command fixes only manual records and does not affect on the radio interface with active protocol MINT . Be careful when entering this command via telnet.
arp [-]proxyall [$ACL]
In "proxyall" mode the system will reply on all ARP requests, if respective IP target address resides in the routing tables and reachable via interface other than source MAC-address. I.e. if there is a route to the target IP then the system can be considered as a gateway.
In "proxyall" mode, you can specify an "$ACL" list of addresses/networks which limits replied ARP requests of the command with networks and addresses of the "$ACL" list.
Example,
arp add 10.10.10.10 00:11:22:33:44:55 arp add 192.168.5.1 5544332211 proxy