show route

Name of the routing table (for example, inet.0).

Number of destinations for which there are routes in the routing table.

Number of routes in the routing table and total number of routes in the following states:

• active (routes that are active).

• holddown (routes that are in the pending state before being declared inactive). A holddown route was once the active route and is no longer the active route. The route is in the holddown state because a protocol still has interest in the route, meaning that the interest bit is set. A protocol might have its interest bit set on the previously active route because the protocol is still advertising the route. The route will be deleted after all protocols withdraw their advertisement of the route and remove their interest bit. A persistent holddown state often means that the interested protocol is not releasing its interest bit properly.

  However, if you have configured advertisement of multiple routes (with the add-path or advertise-inactive statement), the holddown bit is most likely set because BGP is advertising the route as an active route. In this case, you can ignore the holddown state because nothing is wrong.

  If you have configured uRPF-loose mode, the holddown bit is most likely set because Kernel Routing Table (KRT) is using inactive route to build valid incoming interfaces. In this case, you can ignore the holddown state because nothing is wrong.

• hidden (routes that are not used because of a routing policy).

Route destination (for example:10.0.0.1/24). Sometimes the route information is presented in another format, such as:

• MPLS-label (for example, 80001).

• interface-name (for example, ge-1/0/2).

• neighbor-address:control-word-status:encapsulation type:vc-id:source (Layer 2 circuit only. For example, 10.1.1.195:NoCtrlWord:1:1:Local/96):

  • neighbor-address—Address of the neighbor.

  • control-word-status—Whether the use of the control word has been negotiated for this virtual circuit: NoCtrlWord or CtrlWord.

  • encapsulation type—Type of encapsulation, represented by a number: (1) Frame Relay DLCI, (2) ATM AAL5 VCC transport, (3) ATM transparent cell transport, (4) Ethernet, (5) VLAN Ethernet, (6) HDLC, (7) PPP, (8) ATM VCC cell transport, (10) ATM VPC cell transport.

  • vc-id—Virtual circuit identifier.

  • source—Source of the advertisement: Local or Remote.

Protocol from which the route was learned and the preference value for the route.

• +—A plus sign indicates the active route, which is the route installed from the routing table into the forwarding table.

• - —A hyphen indicates the last active route.

• *—An asterisk indicates that the route is both the active and the last active route. An asterisk before a to line indicates the best subpath to the route.

In every routing metric except for the BGP LocalPref attribute, a lesser value is preferred. In order to use common comparison routines, Junos OS stores the 1's complement of the LocalPref value in the Preference2 field. For example, if the LocalPref value for Route 1 is 100, the Preference2 value is -101. If the LocalPref value for Route 2 is 155, the Preference2 value is -156. Route 2 is preferred because it has a higher LocalPref value and a lower Preference2 value.

How long the route been known (for example, 2w4d 13:11:14, or 2 weeks, 4 days, 13 hours, 11 minutes, and 14 seconds).

Cost value of the indicated route. For routes within an AS, the cost is determined by the IGP and the individual protocol metrics. For external routes, destinations, or routing domains, the cost is determined by a preference value.

Local preference value included in the route.

Interface from which the route was received.

AS path through which the route was learned. The letters at the end of the AS path indicate the path origin, providing an indication of the state of the route at the point at which the AS path originated:

• I—IGP.

• E—EGP.

• ?—Incomplete; typically, the AS path was aggregated.

When AS path numbers are included in the route, the format is as follows:

• [ ]—Brackets enclose the local AS number associated with the AS path if more than one AS number is configured on the routing device, or if AS path prepending is configured.

• { }—Braces enclose AS sets, which are groups of AS numbers in which the order does not matter. A set commonly results from route aggregation. The numbers in each AS set are displayed in ascending order.

• ( )—Parentheses enclose a confederation.

• ( [ ] )—Parentheses and brackets enclose a confederation set.

Extended next-hop encoding capability enabled for the specified BGP community for routing IPv4 traffic over IPv6 tunnels. When BGP receives routes without the tunnel community, IPv4-0ver IPv6 tunnels are not created and BGP routes are resolved without encapsulation.

Stack of labels carried in the BGP route update.

(BGP-learned routes) Validation status of the route:

• Invalid—Indicates that the prefix is found, but either the corresponding AS received from the EBGP peer is not the AS that appears in the database, or the prefix length in the BGP update message is longer than the maximum length permitted in the database.

• Unknown—Indicates that the prefix is not among the prefixes or prefix ranges in the database.

• Unverified—Indicates that the origin of the prefix is not verified against the database. This is because the database got populated and the validation is not called for in the BGP import policy, although origin validation is enabled, or the origin validation is not enabled for the BGP peers.

• Valid—Indicates that the prefix and autonomous system pair are found in the database.

Next hop to the destination. An angle bracket (>) indicates that the route is the selected route.

If the destination is Discard, traffic is dropped.

Interface used to reach the next hop. If there is more than one interface available to the next hop, the interface that is actually used is followed by the word Selected. This field can also contain the following information:

• Weight—Value used to distinguish primary, secondary, and fast reroute backup routes. Weight information is available when MPLS label-switched path (LSP) link protection, node-link protection, or fast reroute is enabled, or when the standby state is enabled for secondary paths. A lower weight value is preferred. Among routes with the same weight value, load balancing is possible.

• Balance—Balance coefficient indicating how traffic of unequal cost is distributed among next hops when a routing device is performing unequal-cost load balancing. This information is available when you enable BGP multipath load balancing.

• lsp-path-name—Name of the LSP used to reach the next hop.

• label-action—MPLS label and operation occurring at the next hop. The operation can be pop (where a label is removed from the top of the stack), push (where another label is added to the label stack), or swap (where a label is replaced by another label). For VPNs, expect to see multiple push operations, corresponding to the inner and outer labels required for VPN routes (in the case of a direct PE-to-PE connection, the VPN route would have the inner label push only).

(Enhanced subscriber management for MX Series routers) Indicates that an access-internal route is managed by enhanced subscriber management. By contrast, access-internal routes not managed by enhanced subscriber management are displayed with associated next-hop and media access control (MAC) address information.

Distribution of the load based on the underlying operational interface bandwidth for equal-cost multipaths (ECMP) across the nexthop gateways in percentages.

Count of valid routes in the local routing information base (RIB).

Count of invalid routes due to origin-as mismatch in the local RIB.

Count of invalid routes due to maximum-length mismatch in the local RIB.

Count of unknown routes in the local RIB.