Trying to discover IPs used on a subnet. The subnet does not have any firewalls, etc. Purely access layer switches attached to the router port and hosts attached to the switches (think remote office setup).
What does the router use to determine putting incomplete vs "no entry" in the sh arp? BTW there is other live traffic through the router onto the segment, so the tcl ping script may not have been the packet to cause the original arp request to populate the arp cache.
Thanks.
Use tcl script similar to this to ping sweep segment:
tclsh
for { set i 1 } { $i <= 254 } { incr i } {
ping 172.16.233.$i re 3
}
Then do a sh arp and get response similar to this:
show ip arp
Protocol Address Age(min) Hardware Addr Type Interface
Internet 172.16.233.22 9 0000.0c59.f892 ARPA FastEthernet0/0
Internet 172.16.233.21 8 0000.0c07.ac00 ARPA FastEthernet0/0
Internet 172.16.233.19 - 0000.0c63.1300 ARPA FastEthernet0/0
Internet 172.16.233.30 9 0000.0c36.6965 ARPA FastEthernet0/0
Internet 172.16.168.11 - 0000.0c63.1300 ARPA FastEthernet0/0
Internet 172.16.233.32 0 Incomplete ARPA
Internet 172.16.168.254 9 0000.0c36.6965 ARPA FastEthernet0/0
