ARP CACHE

The cache can be viewed with the following command

#ip neighbor list
192.168.48.1 dev eth0 lladdr 00:50:56:c0:00:08 REACHABLE
192.168.48.190 dev eth0 lladdr 00:0c:29:5e:1c:46 REACHABLE

The cache can be flushed with this command
#ip neighbor flush dev eth0

The follwing settings can be modified
# sysctl  -a | grep "4.neigh.default.gc"
net.ipv4.neigh.default.gc_thresh3 = 1024 #This is the HARD upper limit
net.ipv4.neigh.default.gc_thresh2 = 512   #This is the SOFT upper limit
net.ipv4.neigh.default.gc_thresh1 = 128
net.ipv4.neigh.default.gc_interval = 30      #This is the garbage collection interval in seconds
net.ipv4.neigh.default.gc_stale_time = 60
You will only need to adjust the limits if you need to allow for lots of simultaneous connections