[CentOS] so many arp caches why?

Thu Aug 6 18:58:59 UTC 2009
Les Mikesell <lesmikesell at gmail.com>

MontyRee wrote:
>  
> Hello, all.
>  
>  
> When I execute arp -a -n, there are lots of arp caches like below.
> Surely, I set netmask and Broadcast without problem and routing table also no problem.
>  
> System is CentOS release 4.7 i386.
>  
> I know how to delete the arp cache, 
> but I don't know why ..
>  
>  
> #  ifconfig
> eth0      Link encap:Ethernet  HWaddr 00:A0:D1:E7:91:CC
>           inet addr:192.168.195.36  Bcast:192.168.195.63  Mask:255.255.255.192
> 
> # route -n 
> 192.168.195.0    0.0.0.0          255.255.255.192 U     0      0        0 eth0
> 0.0.0.0          192.168.195.36   0.0.0.0         UG    0      0        0 eth0
> 
>  
> # arp -a -n 
> 
> ? (120.88.46.10) at 00:23:5E:12:63:FE [ether] on eth0
> ? (208.80.195.54) at 00:23:5E:12:63:FE [ether] on eth0
> ? (125.122.171.33) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.233.26.29) at 00:23:5E:12:63:FE [ether] on eth0
> ? (111.125.201.75) at 00:23:5E:12:63:FE [ether] on eth0
> ? (218.24.196.100) at 00:23:5E:12:63:FE [ether] on eth0
> ? (60.190.216.31) at 00:23:5E:12:63:FE [ether] on eth0
> ? (72.232.223.58) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.39.135.185) at 00:23:5E:12:63:FE [ether] on eth0
> ? (203.171.229.153) at 00:23:5E:12:63:FE [ether] on eth0
> ? (121.11.81.217) at 00:23:5E:12:63:FE [ether] on eth0
> ? (61.110.195.18) at 00:11:43:E0:7D:19 [ether] on eth0
> ? (61.164.112.5) at 00:23:5E:12:63:FE [ether] on eth0
> ? (218.66.79.152) at 00:23:5E:12:63:FE [ether] on eth0
> ? (221.139.48.11) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.233.26.12) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.137.175.2) at 00:23:5E:12:63:FE [ether] on eth0
> ? (116.71.174.203) at 00:23:5E:12:63:FE [ether] on eth0
> ? (72.18.205.157) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.39.136.4) at 00:23:5E:12:63:FE [ether] on eth0
> ? (202.255.47.226) at 00:23:5E:12:63:FE [ether] on eth0
> ? (211.211.52.134) at 00:23:5E:12:63:FE [ether] on eth0
> ? (218.61.2.197) at 00:23:5E:12:63:FE [ether] on eth0
> ? (61.164.151.12) at 00:23:5E:12:63:FE [ether] on eth0

Some other device on the subnet is doing proxy arp.

-- 
  Les Mikesell
   lesmikesell at gmail.com