annoying log, received route with strange next hop, Netlink File exists

[LIU Chris via Bird-users]

Classified as: {Hitachi Rail - Public}

Basically configured bird as below

protocol device  {
            scan time 10;
}

protocol kernel {
         scan time 10;
          learn;
          ipv4  {
                       export filter XXXX;
          }
}

bgp and bfd are established, everything is fine.
But only have some annoying log:

Every 10 seconds to print below bird log, assuming this is caused by kernel 
protocol scan time 10.  But why Netlink : File exists, it would write to kernel 
???
KRT:     Received route xx.yy.zz.0/24 with strange next-hop 10.0.0.1
Netlink: File exists

Chris



{Hitachi Rail - Public}