- play_arrow Configuring Firewall Filters
- play_arrow Understanding How Firewall Filters Protect Your Network
- Firewall Filters Overview
- Router Data Flow Overview
- Stateless Firewall Filter Overview
- Understanding How to Use Standard Firewall Filters
- Understanding How Firewall Filters Control Packet Flows
- Stateless Firewall Filter Components
- Stateless Firewall Filter Application Points
- How Standard Firewall Filters Evaluate Packets
- Understanding Firewall Filter Fast Lookup Filter
- Understanding Egress Firewall Filters with PVLANs
- Selective Class-based Filtering on PTX Routers
- Guidelines for Configuring Firewall Filters
- Guidelines for Applying Standard Firewall Filters
- Supported Standards for Filtering
- Monitoring Firewall Filter Traffic
- Troubleshooting Firewall Filters
- play_arrow Firewall Filter Match Conditions and Actions
- Overview of Firewall Filters (OCX Series)
- Overview of Firewall Filter Profiles on ACX Series Routers (Junos OS Evolved)
- Understanding Firewall Filter Match Conditions
- Understanding Firewall Filter Planning
- Understanding How Firewall Filters Are Evaluated
- Understanding Firewall Filter Match Conditions
- Firewall Filter Flexible Match Conditions
- Firewall Filter Nonterminating Actions
- Firewall Filter Terminating Actions
- Firewall Filter Match Conditions and Actions (ACX Series Routers)
- Firewall Filter Match Conditions and Actions in ACX Series Routers (Junos OS Evolved)
- Firewall Filter Match Conditions for Protocol-Independent Traffic
- Firewall Filter Match Conditions for IPv4 Traffic
- Firewall Filter Match Conditions for IPv6 Traffic
- Firewall Filter Match Conditions Based on Numbers or Text Aliases
- Firewall Filter Match Conditions Based on Bit-Field Values
- Firewall Filter Match Conditions Based on Address Fields
- Firewall Filter Match Conditions Based on Address Classes
- Understanding IP-Based Filtering and Selective Port Mirroring of MPLS Traffic
- Firewall Filter Match Conditions for MPLS Traffic
- Firewall Filter Match Conditions for MPLS-Tagged IPv4 or IPv6 Traffic
- Firewall Filter Match Conditions for VPLS Traffic
- Firewall Filter Match Conditions for Layer 2 CCC Traffic
- Firewall Filter Match Conditions for Layer 2 Bridging Traffic
- Firewall Filter Support on Loopback Interface
- play_arrow Applying Firewall Filters to Routing Engine Traffic
- Configuring Logical Units on the Loopback Interface for Routing Instances in Layer 3 VPNs
- Example: Configuring a Filter to Limit TCP Access to a Port Based On a Prefix List
- Example: Configuring a Stateless Firewall Filter to Accept Traffic from Trusted Sources
- Example: Configure a Filter to Block Telnet and SSH Access
- Example: Configuring a Filter to Block TFTP Access
- Example: Configuring a Filter to Accept Packets Based on IPv6 TCP Flags
- Example: Configuring a Filter to Block TCP Access to a Port Except from Specified BGP Peers
- Example: Configuring a Stateless Firewall Filter to Protect Against TCP and ICMP Floods
- Example: Protecting the Routing Engine with a Packets-Per-Second Rate Limiting Filter
- Example: Configuring a Filter to Exclude DHCPv6 and ICMPv6 Control Traffic for LAC Subscriber
- Port Number Requirements for DHCP Firewall Filters
- Example: Configuring a DHCP Firewall Filter to Protect the Routing Engine
- play_arrow Applying Firewall Filters to Transit Traffic
- Example: Configuring a Filter for Use as an Ingress Queuing Filter
- Example: Configuring a Filter to Match on IPv6 Flags
- Example: Configuring a Filter to Match on Port and Protocol Fields
- Example: Configuring a Filter to Count Accepted and Rejected Packets
- Example: Configuring a Filter to Count and Discard IP Options Packets
- Example: Configuring a Filter to Count IP Options Packets
- Example: Configuring a Filter to Count and Sample Accepted Packets
- Example: Configuring a Filter to Set the DSCP Bit to Zero
- Example: Configuring a Filter to Set the DSCP Bit to Zero
- Example: Configuring a Filter to Match on Two Unrelated Criteria
- Example: Configuring a Filter to Accept DHCP Packets Based on Address
- Example: Configuring a Filter to Accept OSPF Packets from a Prefix
- Example: Configuring a Stateless Firewall Filter to Handle Fragments
- Configuring a Firewall Filter to Prevent or Allow IPv4 Packet Fragmentation
- Configuring a Firewall Filter to Discard Ingress IPv6 Packets with a Mobility Extension Header
- Example: Configuring an Egress Filter Based on IPv6 Source or Destination IP Addresses
- Example: Configuring a Rate-Limiting Filter Based on Destination Class
- play_arrow Configuring Firewall Filters in Logical Systems
- Firewall Filters in Logical Systems Overview
- Guidelines for Configuring and Applying Firewall Filters in Logical Systems
- References from a Firewall Filter in a Logical System to Subordinate Objects
- References from a Firewall Filter in a Logical System to Nonfirewall Objects
- References from a Nonfirewall Object in a Logical System to a Firewall Filter
- Example: Configuring Filter-Based Forwarding
- Example: Configuring Filter-Based Forwarding on Logical Systems
- Example: Configuring a Stateless Firewall Filter to Protect a Logical System Against ICMP Floods
- Example: Configuring a Stateless Firewall Filter to Protect a Logical System Against ICMP Floods
- Unsupported Firewall Filter Statements for Logical Systems
- Unsupported Actions for Firewall Filters in Logical Systems
- Filter-Based Forwarding for Routing Instances
- Forwarding Table Filters for Routing Instances on ACX Series Routers
- Configuring Forwarding Table Filters
- play_arrow Configuring Firewall Filter Accounting and Logging
- play_arrow Attaching Multiple Firewall Filters to a Single Interface
- Applying Firewall Filters to Interfaces
- Configuring Firewall Filters
- Multifield Classifier Example: Configuring Multifield Classification
- Multifield Classifier for Ingress Queuing on MX Series Routers with MPC
- Assigning Multifield Classifiers in Firewall Filters to Specify Packet-Forwarding Behavior (CLI Procedure)
- Understanding Multiple Firewall Filters in a Nested Configuration
- Guidelines for Nesting References to Multiple Firewall Filters
- Understanding Multiple Firewall Filters Applied as a List
- Guidelines for Applying Multiple Firewall Filters as a List
- Example: Applying Lists of Multiple Firewall Filters
- Example: Nesting References to Multiple Firewall Filters
- Example: Filtering Packets Received on an Interface Set
- play_arrow Attaching a Single Firewall Filter to Multiple Interfaces
- Interface-Specific Firewall Filter Instances Overview
- Interface-Specific Firewall Filter Instances Overview
- Filtering Packets Received on a Set of Interface Groups Overview
- Filtering Packets Received on an Interface Set Overview
- Example: Configuring Interface-Specific Firewall Filter Counters
- Example: Configuring a Stateless Firewall Filter on an Interface Group
- play_arrow Configuring Filter-Based Tunneling Across IP Networks
- Understanding Filter-Based Tunneling Across IPv4 Networks
- Firewall Filter-Based L2TP Tunneling in IPv4 Networks Overview
- Interfaces That Support Filter-Based Tunneling Across IPv4 Networks
- Components of Filter-Based Tunneling Across IPv4 Networks
- Example: Transporting IPv6 Traffic Across IPv4 Using Filter-Based Tunneling
- play_arrow Configuring Service Filters
- Service Filter Overview
- How Service Filters Evaluate Packets
- Guidelines for Configuring Service Filters
- Guidelines for Applying Service Filters
- Example: Configuring and Applying Service Filters
- Service Filter Match Conditions for IPv4 or IPv6 Traffic
- Service Filter Nonterminating Actions
- Service Filter Terminating Actions
- play_arrow Configuring Simple Filters
- play_arrow Configuring Layer 2 Firewall Filters
- Understanding Firewall Filters Used to Control Traffic Within Bridge Domains and VPLS Instances
- Example: Configuring Filtering of Frames by MAC Address
- Example: Configuring Filtering of Frames by IEEE 802.1p Bits
- Example: Configuring Filtering of Frames by Packet Loss Priority
- Example: Configuring Policing and Marking of Traffic Entering a VPLS Core
- Understanding Firewall Filters on OVSDB-Managed Interfaces
- Example: Applying a Firewall Filter to OVSDB-Managed Interfaces
- play_arrow Configuring Firewall Filters for Forwarding, Fragments, and Policing
- Filter-Based Forwarding Overview
- Firewall Filters That Handle Fragmented Packets Overview
- Stateless Firewall Filters That Reference Policers Overview
- Example: Configuring Filter-Based Forwarding on the Source Address
- Example: Configuring Filter-Based Forwarding to a Specific Outgoing Interface or Destination IP Address
- play_arrow Configuring Firewall Filters (EX Series Switches)
- Firewall Filters for EX Series Switches Overview
- Understanding Planning of Firewall Filters
- Understanding Firewall Filter Match Conditions
- Understanding How Firewall Filters Control Packet Flows
- Understanding How Firewall Filters Are Evaluated
- Understanding Firewall Filter Processing Points for Bridged and Routed Packets on EX Series Switches
- Firewall Filter Match Conditions, Actions, and Action Modifiers for EX Series Switches
- Platform Support for Firewall Filter Match Conditions, Actions, and Action Modifiers on EX Series Switches
- Support for Match Conditions and Actions for Loopback Firewall Filters on Switches
- Configuring Firewall Filters (CLI Procedure)
- Understanding How Firewall Filters Test a Packet's Protocol
- Understanding Filter-Based Forwarding for EX Series Switches
- Example: Configuring Firewall Filters for Port, VLAN, and Router Traffic on EX Series Switches
- Example: Configuring a Firewall Filter on a Management Interface on an EX Series Switch
- Example: Using Filter-Based Forwarding to Route Application Traffic to a Security Device
- Example: Applying Firewall Filters to Multiple Supplicants on Interfaces Enabled for 802.1X or MAC RADIUS Authentication
- Verifying That Policers Are Operational
- Troubleshooting Firewall Filters
- play_arrow Configuring Firewall Filters (QFX Series Switches, EX4600 Switches, PTX Series Routers)
- Overview of Firewall Filters (QFX Series)
- Understanding Firewall Filter Planning
- Planning the Number of Firewall Filters to Create
- Firewall Filter Match Conditions and Actions (QFX and EX Series Switches)
- Firewall Filter Match Conditions and Actions (QFX10000 Switches)
- Firewall Filter Match Conditions and Actions (PTX Series Routers)
- Firewall and Policing Differences Between PTX Series Packet Transport Routers and T Series Matrix Routers
- Configuring Firewall Filters
- Applying Firewall Filters to Interfaces
- Overview of MPLS Firewall Filters on Loopback Interface
- Configuring MPLS Firewall Filters and Policers on Switches
- Configuring MPLS Firewall Filters and Policers on Routers
- Configuring MPLS Firewall Filters and Policers
- Understanding How a Firewall Filter Tests a Protocol
- Understanding Firewall Filter Processing Points for Bridged and Routed Packets
- Understanding Filter-Based Forwarding
- Example: Using Filter-Based Forwarding to Route Application Traffic to a Security Device
- Configuring a Firewall Filter to De-Encapsulate GRE or IPIP Traffic
- Verifying That Firewall Filters Are Operational
- Monitoring Firewall Filter Traffic
- Troubleshooting Firewall Filter Configuration
- play_arrow Configuring Firewall Filter Accounting and Logging (EX9200 Switches)
-
- play_arrow Configuring Traffic Policers
- play_arrow Understanding Traffic Policers
- Policer Implementation Overview
- ARP Policer Overview
- Example: Configuring ARP Policer
- Understanding the Benefits of Policers and Token Bucket Algorithms
- Determining Proper Burst Size for Traffic Policers
- Controlling Network Access Using Traffic Policing Overview
- Traffic Policer Types
- Order of Policer and Firewall Filter Operations
- Understanding the Frame Length for Policing Packets
- Supported Standards for Policing
- Hierarchical Policer Configuration Overview
- Understanding Enhanced Hierarchical Policers
- Packets-Per-Second (pps)-Based Policer Overview
- Guidelines for Applying Traffic Policers
- Policer Support for Aggregated Ethernet Interfaces Overview
- Example: Configuring a Physical Interface Policer for Aggregate Traffic at a Physical Interface
- Firewall and Policing Differences Between PTX Series Packet Transport Routers and T Series Matrix Routers
- Hierarchical Policers on ACX Series Routers Overview
- Guidelines for Configuring Hierarchical Policers on ACX Series Routers
- Hierarchical Policer Modes on ACX Series Routers
- Processing of Hierarchical Policers on ACX Series Routers
- Actions Performed for Hierarchical Policers on ACX Series Routers
- Configuring Aggregate Parent and Child Policers on ACX Series Routers
- play_arrow Configuring Policer Rate Limits and Actions
- play_arrow Configuring Layer 2 Policers
- Hierarchical Policers
- Configuring a Policer Overhead
- Two-Color and Three-Color Policers at Layer 2
- Layer 2 Traffic Policing at the Pseudowire Overview
- Configuring a Two-Color Layer 2 Policer for the Pseudowire
- Configuring a Three-Color Layer 2 Policer for the Pseudowire
- Applying the Policers to Dynamic Profile Interfaces
- Attaching Dynamic Profiles to Routing Instances
- Using Variables for Layer 2 Traffic Policing at the Pseudowire Overview
- Configuring a Policer for the Complex Configuration
- Creating a Dynamic Profile for the Complex Configuration
- Attaching Dynamic Profiles to Routing Instances for the Complex Configuration
- Verifying Layer 2 Traffic Policers on VPLS Connections
- Understanding Policers on OVSDB-Managed Interfaces
- Example: Applying a Policer to OVSDB-Managed Interfaces
- play_arrow Configuring Two-Color and Three-Color Traffic Policers at Layer 3
- Two-Color Policer Configuration Overview
- Basic Single-Rate Two-Color Policers
- Bandwidth Policers
- Prefix-Specific Counting and Policing Actions
- Policer Overhead to Account for Rate Shaping in the Traffic Manager
- Three-Color Policer Configuration Overview
- Applying Policers
- Three-Color Policer Configuration Guidelines
- Basic Single-Rate Three-Color Policers
- Basic Two-Rate Three-Color Policers
- Example: Configuring a Two-Rate Three-Color Policer
- play_arrow Configuring Logical and Physical Interface Traffic Policers at Layer 3
- play_arrow Configuring Policers on Switches
- Overview of Policers
- Traffic Policer Types
- Understanding the Use of Policers in Firewall Filters
- Understanding Tricolor Marking Architecture
- Configuring Policers to Control Traffic Rates (CLI Procedure)
- Configuring Tricolor Marking Policers
- Understanding Policers with Link Aggregation Groups
- Understanding Color-Blind Mode for Single-Rate Tricolor Marking
- Understanding Color-Aware Mode for Single-Rate Tricolor Marking
- Understanding Color-Blind Mode for Two-Rate Tricolor Marking
- Understanding Color-Aware Mode for Two-Rate Tricolor Marking
- Example: Using Two-Color Policers and Prefix Lists
- Example: Using Policers to Manage Oversubscription
- Assigning Forwarding Classes and Loss Priority
- Configuring Color-Blind Egress Policers for Medium-Low PLP
- Configuring Two-Color and Three-Color Policers to Control Traffic Rates
- Verifying That Two-Color Policers Are Operational
- Verifying That Three-Color Policers Are Operational
- Troubleshooting Policer Configuration
- Troubleshooting Policer Configuration
-
- play_arrow Configuration Statements and Operational Commands
- play_arrow Troubleshooting
- play_arrow Knowledge Base
-
ON THIS PAGE
Example: Applying Routing Policies at Different Levels of the BGP Hierarchy
This example shows BGP configured in a simple network topology and explains how routing polices take effect when they are applied at different levels of the BGP configuration.
Requirements
No special configuration beyond device initialization is required before configuring this example.
Overview
For BGP, you can apply policies as follows:
BGP global
import
andexport
statements—Include these statements at the[edit protocols bgp]
hierarchy level (for routing instances, include these statements at the[edit routing-instances routing-instance-name protocols bgp]
hierarchy level).Group
import
andexport
statements—Include these statements at the[edit protocols bgp group group-name]
hierarchy level (for routing instances, include these statements at the[edit routing-instances routing-instance-name protocols bgp group group-name]
hierarchy level).Peer
import
andexport
statements—Include these statements at the[edit protocols bgp group group-name neighbor address]
hierarchy level (for routing instances, include these statements at the[edit routing-instances routing-instance-name protocols bgp group group-name neighbor address]
hierarchy level).
A peer-level import
or export
statement overrides a group import
or export
statement. A group-level import
or export
statement overrides a global BGP import
or export
statement.
In this example, a policy named send-direct
is applied at the global level,
another policy named send-192.168.0.1
is applied at the group level, and a third
policy named send-192.168.20.1
is applied at the neighbor level.
user@host# show protocols bgp { local-address 172.16.1.1; export send-direct; group internal-peers { type internal; export send-192.168.0.1; neighbor 172.16.2.2 { export send-192.168.20.1; } neighbor 172.16.3.3; } group other-group { type internal; neighbor 172.16.4.4; } }
A key point, and one that is often misunderstood and that can lead to problems, is that in such a configuration, only the most explicit policy is applied. A neighbor-level policy is more explicit than a group-level policy, which in turn is more explicit than a global policy.
The neighbor 172.16.2.2 is subjected only to the send-192.168.20.1 policy. The neighbor 172.16.3.3, lacking anything more specific, is subjected only to the send-192.168.0.1 policy. Meanwhile, neighbor 172.16.4.4 in group other-group has no group or neighbor-level policy, so it uses the send-direct policy.
If you need to have neighbor 172.16.2.2 perform the function of all three policies, you can write and apply a new neighbor-level policy that encompasses the functions of the other three, or you can apply all three existing policies, as a chain, to neighbor 172.16.2.2.
Topology
Figure 1 shows the sample network.

CLI Quick Configuration shows the configuration for all of the devices in Figure 1.
The section #configuration__policy-bgp-apply-levels-st describes the steps on Device R1.
Configuration
CLI Quick Configuration
To quickly configure this example,
copy the following commands, paste them into a text file, remove any line breaks, change any
details necessary to match your network configuration, and then copy and paste the commands
into the CLI at the [edit]
hierarchy level.
Device R1
set interfaces fe-1/2/0 unit 0 description to-R2 set interfaces fe-1/2/0 unit 0 family inet address 10.10.10.1/30 set interfaces lo0 unit 0 family inet address 172.16.1.1/32 set protocols bgp local-address 172.16.1.1 set protocols bgp export send-direct set protocols bgp group internal-peers type internal set protocols bgp group internal-peers export send-static-192.168.0 set protocols bgp group internal-peers neighbor 172.16.2.2 export send-static-192.168.20 set protocols bgp group internal-peers neighbor 172.16.3.3 set protocols bgp group other-group type internal set protocols bgp group other-group neighbor 172.16.4.4 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/0.0 set policy-options policy-statement send-direct term 1 from protocol direct set policy-options policy-statement send-direct term 1 then accept set policy-options policy-statement send-static-192.168.0 term 1 from protocol static set policy-options policy-statement send-static-192.168.0 term 1 from route-filter 192.168.0.0/24 orlonger set policy-options policy-statement send-static-192.168.0 term 1 then accept set policy-options policy-statement send-static-192.168.20 term 1 from protocol static set policy-options policy-statement send-static-192.168.20 term 1 from route-filter 192.168.20.0/24 orlonger set policy-options policy-statement send-static-192.168.20 term 1 then accept set routing-options static route 192.168.0.1/32 discard set routing-options static route 192.168.20.1/32 discard set routing-options router-id 172.16.1.1 set routing-options autonomous-system 17
Device R2
set interfaces fe-1/2/0 unit 0 description to-R1 set interfaces fe-1/2/0 unit 0 family inet address 10.10.10.2/30 set interfaces fe-1/2/1 unit 0 description to-R3 set interfaces fe-1/2/1 unit 0 family inet address 10.10.10.5/30 set interfaces lo0 unit 0 family inet address 172.16.2.2/32 set protocols bgp group internal-peers type internal set protocols bgp group internal-peers local-address 172.16.2.2 set protocols bgp group internal-peers neighbor 172.16.3.3 set protocols bgp group internal-peers neighbor 172.16.1.1 set protocols bgp group internal-peers neighbor 172.16.4.4 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/0.0 set protocols ospf area 0.0.0.0 interface fe-1/2/1.0 set routing-options router-id 172.16.2.2 set routing-options autonomous-system 17
Device R3
set interfaces fe-1/2/1 unit 0 description to-R2 set interfaces fe-1/2/1 unit 0 family inet address 10.10.10.6/30 set interfaces fe-1/2/2 unit 0 description to-R4 set interfaces fe-1/2/2 unit 0 family inet address 10.10.10.9/30 set interfaces lo0 unit 0 family inet address 172.16.3.3/32 set protocols bgp group internal-peers type internal set protocols bgp group internal-peers local-address 172.16.3.3 set protocols bgp group internal-peers neighbor 172.16.2.2 set protocols bgp group internal-peers neighbor 172.16.1.1 set protocols bgp group internal-peers neighbor 172.16.4.4 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/1.0 set protocols ospf area 0.0.0.0 interface fe-1/2/2.0 set routing-options router-id 172.16.3.3 set routing-options autonomous-system 17
Device R4
set interfaces fe-1/2/2 unit 0 description to-R3 set interfaces fe-1/2/2 unit 0 family inet address 10.10.10.10/30 set interfaces lo0 unit 0 family inet address 172.16.4.4/32 set protocols bgp group internal-peers type internal set protocols bgp group internal-peers local-address 172.16.4.4 set protocols bgp group internal-peers neighbor 172.16.2.2 set protocols bgp group internal-peers neighbor 172.16.1.1 set protocols bgp group internal-peers neighbor 172.16.3.3 set protocols ospf area 0.0.0.0 interface lo0.0 passive set protocols ospf area 0.0.0.0 interface fe-1/2/2.0 set routing-options router-id 172.16.4.4 set routing-options autonomous-system 17
Procedure
Step-by-Step Procedure
The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.
To configure an IS-IS default route policy:
Configure the device interfaces.
content_copy zoom_out_map[edit interfaces] user@R1# set fe-1/2/0 unit 0 description to-R2 user@R1# set fe-1/2/0 unit 0 family inet address 10.10.10.1/30 user@R1# set lo0 unit 0 family inet address 172.16.1.1/32
Enable OSPF, or another interior gateway protocols (IGP), on the interfaces.
content_copy zoom_out_map[edit protocols OSPF area 0.0.0.0] user@R1# set interface lo0.0 passive user@R1# set interface fe-1/2/0.0
Configure static routes.
content_copy zoom_out_map[edit routing-options] user@R1# set static route 192.168.0.1/32 discard user@R1# set static route 192.168.20.1/32 discard
Enable the routing policies.
content_copy zoom_out_map[edit protocols policy-options] user@R1# set policy-statement send-direct term 1 from protocol direct user@R1# set policy-statement send-direct term 1 then accept user@R1# set policy-statement send-static-192.168.0 term 1 from protocol static user@R1# set policy-statement send-static-192.168.0 term 1 from route-filter 192.168.0.0/24 orlonger user@R1# set policy-statement send-static-192.168.0 term 1 then accept user@R1# set policy-statement send-static-192.168.20 term 1 from protocol static user@R1# set policy-statement send-static-192.168.20 term 1 from route-filter 192.168.20.0/24 orlonger user@R1# set policy-statement send-static-192.168.20 term 1 then accept
Configure BGP and apply the export policies.
content_copy zoom_out_map[edit protocols bgp] user@R1# set local-address 172.16.1.1 user@R1# set protocols bgp export send-direct user@R1# set group internal-peers type internal user@R1# set group internal-peers export send-static-192.168.0 user@R1# set group internal-peers neighbor 172.16.2.2 export send-static-192.168.20 user@R1# set group internal-peers neighbor 172.16.3.3 user@R1# set group other-group type internal user@R1# set group other-group neighbor 172.16.4.4
Configure the router ID and autonomous system (AS) number.
content_copy zoom_out_map[edit routing-options] user@R1# set router-id 172.16.1.1 user@R1# set autonomous-system 17
If you are done configuring the device, commit the configuration.
content_copy zoom_out_map[edit] user@R1# commit
Results
From configuration mode, confirm your configuration by issuing the show interfaces
, show protocols
, show policy-options
, and show routing-options
commands. If the output does not display the intended configuration, repeat the instructions
in this example to correct the configuration.
user@R1# show interfaces fe-1/2/0 { unit 0 { description to-R2; family inet { address 10.10.10.1/30; } } } lo0 { unit 0 { family inet { address 172.16.1.1/32; } } }
user@R1# show protocols bgp { local-address 172.16.1.1; export send-direct; group internal-peers { type internal; export send-static-192.168.0; neighbor 172.16.2.2 { export send-static-192.168.20; } neighbor 172.16.3.3; } group other-group { type internal; neighbor 172.16.4.4; } } ospf { area 0.0.0.0 { interface lo0.0 { passive; } interface fe-1/2/0.0; } }
user@R1# show policy-options policy-statement send-direct { term 1 { from protocol direct; then accept; } } policy-statement send-static-192.168.0 { term 1 { from { protocol static; route-filter 192.168.0.0/24 orlonger; } then accept; } } policy-statement send-static-192.168.20 { term 1 { from { protocol static; route-filter 192.168.20.0/24 orlonger; } then accept; } }
user@R1# show routing-options static { route 192.168.0.1/32 discard; route 192.168.20.1/32 discard; } router-id 172.16.1.1; autonomous-system 17;
Verification
Confirm that the configuration is working properly.
Verifying BGP Route Learning
Purpose
Make sure that the BGP export policies are working as expected by checking the routing tables.
Action
user@R1> show route protocol direct inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 172.16.1.1/32 *[Direct/0] 1d 22:19:47 > via lo0.0 10.10.10.0/30 *[Direct/0] 1d 22:19:47 > via fe-1/2/0.0
user@R1> show route protocol static inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 192.168.0.1/32 *[Static/5] 02:20:03 Discard 192.168.20.1/32 *[Static/5] 02:20:03 Discard
user@R2> show route protocol bgp inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 192.168.20.1/32 *[BGP/170] 02:02:40, localpref 100, from 172.16.1.1 AS path: I, validation-state: unverified > to 10.10.10.1 via fe-1/2/0.0
user@R3> show route protocol bgp inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 192.168.0.1/32 *[BGP/170] 02:02:51, localpref 100, from 172.16.1.1 AS path: I, validation-state: unverified > to 10.10.10.5 via fe-1/2/1.0
user@R4> show route protocol bgp inet.0: 9 destinations, 11 routes (9 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 172.16.1.1/32 [BGP/170] 1d 20:38:54, localpref 100, from 172.16.1.1 AS path: I, validation-state: unverified > to 10.10.10.9 via fe-1/2/2.0 10.10.10.0/30 [BGP/170] 1d 20:38:54, localpref 100, from 172.16.1.1 AS path: I, validation-state: unverified > to 10.10.10.9 via fe-1/2/2.0
Meaning
On Device R1, the show route protocol direct
command displays two
direct routes: 172.16.1.1/32 and 10.10.10.0/30. The show route protocol static
command displays two static routes: 192.168.0.1/32 and 192.168.20.1/32.
On Device R2, the show route protocol bgp
command shows that the only route
that Device R2 has learned through BGP is the 192.168.20.1/32 route.
On Device R3, the show route protocol bgp
command shows that the only route
that Device R3 has learned through BGP is the 192.168.0.1/32 route.
On Device R4, the show route protocol bgp
command shows that the only routes
that Device R4 has learned through BGP are the 172.16.1.1/32 and 10.10.10.0/30 routes.
Verifying BGP Route Receiving
Purpose
Make sure that the BGP export policies are working as expected by checking the BGP routes received from Device R1.
Action
user@R2> show route receive-protocol bgp 172.16.1.1 inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) Prefix Nexthop MED Lclpref AS path * 192.168.20.1/32 172.16.1.1 100 I
user@R3> show route receive-protocol bgp 172.16.1.1 inet.0: 11 destinations, 11 routes (11 active, 0 holddown, 0 hidden) Prefix Nexthop MED Lclpref AS path * 192.168.0.1/32 172.16.1.1 100 I
user@R4> show route receive-protocol bgp 172.16.1.1 inet.0: 9 destinations, 11 routes (9 active, 0 holddown, 0 hidden) Prefix Nexthop MED Lclpref AS path 172.16.1.1/32 172.16.1.1 100 I 10.10.10.0/30 172.16.1.1 100 I
Meaning
On Device R2, the route receive-protocol bgp 172.16.1.1
command
shows that Device R2 received only one BGP route, 192.168.20.1/32, from Device R1.
On Device R3, the route receive-protocol bgp 172.16.1.1
command shows that
Device R3 received only one BGP route, 192.168.0.1/32, from Device R1.
On Device R4, the route receive-protocol bgp 172.16.1.1
command shows that
Device R4 received two BGP routes, 172.16.1.1/32 and 10.10.10.0/30, from Device R1.
In summary, when multiple policies are applied at different CLI hierarchies in BGP, only the most specific application is evaluated, to the exclusion of other, less specific policy applications. Although this point might seem to make sense, it is easily forgotten during router configuration, when you mistakenly believe that a neighbor-level policy is combined with a global or group-level policy, only to find that your policy behavior is not as anticipated.