When use CentOS 6.5,kernel version 2.6.431, I have continuous messages of
“Neighbour table overflow” in messages. I have modified the gc_thresh1(512) , gc_thresh2 (2048) gc_thresh3 (4096)
in /proc/sys/net.. path, But the messages occurs occasionally.
some forum saied:
They are probably realted to a kernel bug where the thresholds are in fact only half of the value that is set. See http://patchwork.ozlabs.org/patch/170385/