diff options
| -rw-r--r-- | server/server.go | 2 | ||||
| -rw-r--r-- | table/destination.go | 25 | ||||
| -rw-r--r-- | table/destination_test.go | 36 | ||||
| -rw-r--r-- | table/table_manager_test.go | 1 | ||||
| -rw-r--r-- | test/lib/gobgp.py | 8 |
5 files changed, 69 insertions, 3 deletions
diff --git a/server/server.go b/server/server.go index c774e47e..605d9fe4 100644 --- a/server/server.go +++ b/server/server.go @@ -1660,6 +1660,8 @@ func (server *BgpServer) handleModConfig(grpcReq *GrpcRequest) error { return err } server.bgpConfig.Global = *c + // update route selection options + table.SelectionOptions = c.RouteSelectionOptions.Config case api.Operation_DEL_ALL: for k, _ := range server.neighborMap { _, err := server.handleGrpcModNeighbor(&GrpcRequest{ diff --git a/table/destination.go b/table/destination.go index 131cb129..0e195f83 100644 --- a/table/destination.go +++ b/table/destination.go @@ -27,6 +27,8 @@ import ( "sort" ) +var SelectionOptions config.RouteSelectionOptionsConfig + type BestPathReason string const ( @@ -42,6 +44,7 @@ const ( BPR_ASN BestPathReason = "ASN" BPR_IGP_COST BestPathReason = "IGP Cost" BPR_ROUTER_ID BestPathReason = "Router ID" + BPR_OLDER BestPathReason = "Older" ) func IpToRadixkey(b []byte, max uint8) string { @@ -485,6 +488,10 @@ func (p paths) Less(i, j int) bool { reason = BPR_IGP_COST } if better == nil { + better = compareByAge(path1, path2) + reason = BPR_OLDER + } + if better == nil { var e error = nil better, e = compareByRouterID(path1, path2) if e != nil { @@ -720,11 +727,11 @@ func compareByRouterID(path1, path2 *Path) (*Path, error) { // If both paths are from eBGP peers, then according to RFC we need // not tie break using router id. - if !path1.IsIBGP() && !path2.IsIBGP() { + if !SelectionOptions.ExternalCompareRouterId && !path1.IsIBGP() && !path2.IsIBGP() { return nil, nil } - if path1.IsIBGP() != path2.IsIBGP() { + if !SelectionOptions.ExternalCompareRouterId && path1.IsIBGP() != path2.IsIBGP() { return nil, fmt.Errorf("This method does not support comparing ebgp with ibgp path") } @@ -743,6 +750,20 @@ func compareByRouterID(path1, path2 *Path) (*Path, error) { } } +func compareByAge(path1, path2 *Path) *Path { + if !path1.IsIBGP() && !path2.IsIBGP() && !SelectionOptions.ExternalCompareRouterId { + age1 := path1.info.timestamp.UnixNano() + age2 := path2.info.timestamp.UnixNano() + if age1 == age2 { + return nil + } else if age1 < age2 { + return path1 + } + return path2 + } + return nil +} + func (dest *Destination) String() string { return fmt.Sprintf("Destination NLRI: %s", dest.nlri.String()) } diff --git a/table/destination_test.go b/table/destination_test.go index 32316f5f..c0666e21 100644 --- a/table/destination_test.go +++ b/table/destination_test.go @@ -217,6 +217,42 @@ func TestImplicitWithdrawCalculate(t *testing.T) { assert.Equal(t, len(d.knownPathList), 1) } +func TestTimeTieBreaker(t *testing.T) { + origin := bgp.NewPathAttributeOrigin(0) + aspathParam := []bgp.AsPathParamInterface{bgp.NewAs4PathParam(2, []uint32{65001})} + aspath := bgp.NewPathAttributeAsPath(aspathParam) + nexthop := bgp.NewPathAttributeNextHop("10.0.0.1") + med := bgp.NewPathAttributeMultiExitDisc(0) + pathAttributes := []bgp.PathAttributeInterface{origin, aspath, nexthop, med} + nlri := bgp.NewIPAddrPrefix(24, "10.10.0.0") + updateMsg := bgp.NewBGPUpdateMessage(nil, pathAttributes, []*bgp.IPAddrPrefix{nlri}) + peer1 := &PeerInfo{AS: 2, LocalAS: 1, Address: net.IP{1, 1, 1, 1}, ID: net.IP{1, 1, 1, 1}} + path1 := ProcessMessage(updateMsg, peer1, time.Now())[0] + + peer2 := &PeerInfo{AS: 2, LocalAS: 1, Address: net.IP{2, 2, 2, 2}, ID: net.IP{2, 2, 2, 2}} // weaker router-id + path2 := ProcessMessage(updateMsg, peer2, time.Now().Add(-1*time.Hour))[0] // older than path1 + + d := NewDestination(nlri) + d.addNewPath(path1) + d.addNewPath(path2) + + d.Calculate(nil) + + assert.Equal(t, len(d.knownPathList), 2) + assert.Equal(t, true, d.GetBestPath("").GetSource().ID.Equal(net.IP{2, 2, 2, 2})) // path from peer2 win + + // this option disables tie breaking by age + SelectionOptions.ExternalCompareRouterId = true + d = NewDestination(nlri) + d.addNewPath(path1) + d.addNewPath(path2) + + d.Calculate(nil) + + assert.Equal(t, len(d.knownPathList), 2) + assert.Equal(t, true, d.GetBestPath("").GetSource().ID.Equal(net.IP{1, 1, 1, 1})) // path from peer1 win +} + func DestCreatePeer() []*PeerInfo { peerD1 := &PeerInfo{AS: 65000} peerD2 := &PeerInfo{AS: 65001} diff --git a/table/table_manager_test.go b/table/table_manager_test.go index 21d70d84..8b072c44 100644 --- a/table/table_manager_test.go +++ b/table/table_manager_test.go @@ -1115,6 +1115,7 @@ func TestProcessBGPUpdate_6_select_ebgp_path_ipv6(t *testing.T) { func TestProcessBGPUpdate_7_select_low_routerid_path_ipv4(t *testing.T) { tm := NewTableManager([]bgp.RouteFamily{bgp.RF_IPv4_UC}, 0, 0) + SelectionOptions.ExternalCompareRouterId = true // low origin message origin1 := bgp.NewPathAttributeOrigin(0) diff --git a/test/lib/gobgp.py b/test/lib/gobgp.py index 0b352fa5..b123369e 100644 --- a/test/lib/gobgp.py +++ b/test/lib/gobgp.py @@ -201,7 +201,13 @@ class GoBGPContainer(BGPContainer): self._create_config_zebra() def _create_config_bgp(self): - config = {'global': {'config': {'as': self.asn, 'router-id': self.router_id}}} + config = {'global': {'config': {'as': self.asn, 'router-id': self.router_id}, + 'route-selection-options':{ + 'config': { + 'external-compare-router-id': True, + }, + }, + }} for peer, info in self.peers.iteritems(): afi_safi_list = [] version = netaddr.IPNetwork(info['neigh_addr']).version |