Can not remove FAILED neigh entry??

Hi, all


I am wondering if the following behavior is expected, I can't
manually delete or flush a neigh entry:

[root@localhost ~]# ip -s -s neigh show
192.168.122.1 dev eth0 lladdr 52:54:00:5e:f5:1e used 22/22/5 probes 4 STALE
[root@localhost ~]#
[root@localhost ~]# ip neigh del 192.168.122.1 dev eth0
[root@localhost ~]# ip -s -s neigh show
192.168.122.1 dev eth0  used 34/34/17 probes 4 FAILED
[root@localhost ~]# ip -s -s neigh flush all
Nothing to flush.
[root@localhost ~]# ip -s -s neigh show
192.168.122.1 dev eth0  used 42/42/26 probes 4 FAILED
[root@localhost ~]# sleep 60
[root@localhost ~]# ip -s -s neigh show
192.168.122.1 dev eth0  used 130/130/113 probes 4 FAILED

I thought it would timeout (gc_stale_time) after it becomes FAILED,
but apparently it is still there after a long time. If this is what we expect,
then what's the right way to remove an entry from a neigh table manually?


Thanks!