Configuring Static BGP VPNv6 Flow Specification
Static BGP VPNv6 Flow Specification allows BGP VPNv6 Flow Specification routes to be transmitted and traffic filtering policies to be generated. The policies improve security of devices in VPNs.
Usage Scenario
To deploy static BGP VPNv6 Flow Specification, create a BGP VPN IPv6 Flow Specification route first, and then establish a BGP VPNv6 Flow Specification peer relationship between the device on which the BGP VPN IPv6 Flow Specification route is created and the network ingress to transmit the BGP VPNv6 Flow Specification route.
In an AS with multiple ingresses, a BGP Flow route reflector (Flow RR) can be deployed to reduce the number of BGP VPNv6 Flow Specification peer relationships and save CPU resources.
If you want to filter traffic based on an address prefix and the BGP VPNv6 Flow Specification route carrying the filtering rule fails to be authenticated, disable the authentication of the BGP VPNv6 Flow Specification routes received from a specified peer.
Pre-configuration Tasks
Before configuring static BGP VPNv6 Flow Specification, configure a VPN instance and bind an interface to the VPN instance.
Procedure
- Create a BGP VPN IPv6 Flow Specification route.
- According to the characteristics of the traffic to be controlled, you can configure one or more if-match clauses to define traffic filtering rules as required. Detailed configurations are as follows:
To set a traffic filtering rule that is based on a destination IP address, run the if-match destination ipv6-address ipv6-mask-length command.
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NOTE: If you want to control the traffic destined for a specified IPv6 address and the BGP VPN IPv6 Flow Specification route carrying the filtering rule configured using the if-match destination command fails to be authenticated, run the peer validation-disable command to disable the authentication of BGP VPN IPv6 Flow Specification routes.
By default, 0.0.0.0/0 is used as the prefix in the peer import or export policy against which BGP VPN IPv6 Flow Specification routes are matched. To use a peer import or export policy to match BGP VPN IPv6 Flow Specification routes against the destination IPv6 address specified in the if-match destination command, run the route match-destination command.
To set a traffic filtering rule that is based on a source IP address, run the if-match source ipv6-address ipv6-mask-length command.
To set a traffic filtering rule that is based on a port number, run the if-match port operator port command.
To set a traffic filtering rule that is based on a source port number, run the if-match source-port operator port command.
To set a traffic filtering rule that is based on a destination port number, run the if-match destination-port operator port command.
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NOTE: The if-match port command is mutually exclusive with the if-match destination-port or if-match source-port command.
To set a traffic filtering rule that is based on the protocol used to carry traffic, run the if-match protocol operator protocol command.
To set a traffic filtering rule that is based on a service type, run the if-match dscp operator dscp command.
To set a traffic filtering rule that is based on a TCP flag value, run the if-match tcp-flags { match | not } tcp-flags command.
Network attackers may send a large number of invalid TCP packets to attack network devices. To control the unidirectional traffic of TCP packets for the sake of communication security, you can run the if-match tcp-flags command to match BGP VPN IPv6 Flow Specification routes against a specified TCP flag value. The traffic behavior specified in the apply clause applies to the traffic that matches the TCP flag value.
To set a traffic filtering rule that is based on a packet fragmentation type, run the if-match fragment-type { match | not } fragment-type-name command.
To set a traffic filtering rule that is based on an ICMP packet code, run the if-match icmp-code operator icmp-code command.
To set a traffic filtering rule that is based on an ICMP packet type, run the if-match icmp-type { greater-than | less-than | equal } icmp-type command.
To set a traffic filtering rule that is based on the length of the message carrying the BGP VPN IPv6 Flow Specification route, run the if-match packet-length { greater-than | less-than | equal } packet-length-value command.
- Configure apply clauses to define traffic behaviors as required. Detailed configurations are as follows:
To discard the traffic that matches the specified filtering rules, run the apply deny command.
To redirect the attack traffic that matches the specified filtering rules to a traffic cleaning device or black hole, run the apply redirect vpn-target vpn-target-import } command.
To redefine the service type for the traffic that matches the specified filtering rules, run the apply remark-dscp command.
To limit the rate of the traffic that matches the specified filtering rules, run the apply traffic-rate command.
To sample the traffic that matches the specified filtering rules, run the apply traffic-action sample command.
You can run the apply traffic-action sample command for a BGP VPN IPv6 Flow Specification route to sample the traffic that matches the specified filtering rules. Through sampling, abnormal traffic can be identified and filtered out, which protects the attacked device and improves network security.
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NOTE: The apply deny and apply traffic-rate commands are mutually exclusive.
If a configured BGP VPN IPv6 Flow Specification route does not need to take effect locally, you can run the routing-table rib-only [ route-policy route-policy-name | route-filter route-filter-name ] command to prevent it from being delivered to the FES forwarding table.
- According to the characteristics of the traffic to be controlled, you can configure one or more if-match clauses to define traffic filtering rules as required. Detailed configurations are as follows:
- Establish a BGP VPNv6 Flow Specification peer relationship.
- (Optional) Configure a Flow RR.
Before configuring a Flow RR, establish a BGP VPNv6 Flow Specification peer relationship between the Flow RR and the device on which the BGP VPN IPv6 Flow Specification route is created, and between the Flow RR and the network ingress.
Checking the Configurations
Run the following commands to check the previous configuration.
Run the display bgp flow vpnv6 all peer [ [ ipv4-address ] verbose ] command to check information about all BGP VPNv6 Flow Specification peers.
Run the display bgp flow vpnv6 { all | route-distinguisher route-distinguisher } routing-table [ reindex ] command to check information about all BGP VPNv6 Flow Specification routes or about the BGP VPNv6 Flow Specification routes with a specified RD.
Run the display bgp flow vpnv6 { all | route-distinguisher route-distinguisher } routing-table statistics command to check statistics about all BGP VPNv6 Flow Specification routes or about the BGP VPNv6 Flow Specification routes with a specified RD.
# Run the display bgp flow vpnv6 all peer [ [ ipv4-address ] verbose ] command to check whether the BGP VPNv6 Flow Specification peer relationship is established.
<HUAWEI> display bgp flow vpnv6 all peer
BGP local router ID : 10.2.1.2
Local AS number : 200
Total number of peers : 1 Peers in established state : 1
Peer V AS MsgRcvd MsgSent OutQ Up/Down State PrefRcv
10.2.1.1 4 200 1042 1051 0 15:07:49 Established 0
# Run the display bgp flow vpnv6 { all | route-distinguisher route-distinguisher } routing-table [ reindex ] command to check information about BGP VPNv6 Flow Specification routes.
<HUAWEI> display bgp flow vpnv6 all routing-table 536870913
BGP local router ID : 10.2.1.2
Local AS number : 200
ReIndex : 536870913
Order : 0
Dissemination Rules :
Src. Port : eq 159
BGP flow-vpnv6 routing table entry information of 536870913:
Route Distinguisher: 200:1
Match action :
apply deny
From: 0.0.0.0 (0.0.0.0)
Route Duration: 0d00h02m53s
Ext-Community: RT <111 : 1>
AS-path Nil, origin igp, MED 0, pref-val 0, valid, local, best, pre 255
Advertised to such 1 peers:
10.2.1.1
# Run the display bgp flow vpnv6 { all | route-distinguisher route-distinguisher } routing-table statistics command on the network ingress to check statistics about the BGP VPNv6 Flow Specification routes received from the specified BGP VPNv6 Flow Specification peer.
<HUAWEI> display bgp flow vpnv6 route-distinguisher 200:1 routing-table statistics
Route Distinguisher: 200:1
Total Number of Routes: 1
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