Routing status display

Overview

To cope with the richness of routing functions, status display procedures begin by show routing.

The available show routing commands and arguments may be listed by using the ? character.

Example

router{}show routing <?>
Valid entries at this position are:
  bgp      BGP information
  ip       IP information
  ipv6     IPv6 information
  memory   Memory statistics

router{}show routing ip <?>
Valid entries at this position are:
  bgp     BGP information
  ospf    OSPF information
  rip     Show RIP routes
  route   Routing table

router{}show routing ip rip <?>
Valid entries at this position are:
  <Enter>   Execute command
  status    Process parameters and statistics

router{}show routing ip rip status <?>
Valid entry at this position is:
  <Enter>   Execute command

router{}

Displaying routing protocols status

Displaying RIP status

The show routing ip rip status command displays a summary of RIP protocol status. This is the first thing to do to check whether the RIP session is OK. If RIP protocol is not enabled, nothing will be displayed.

Example

router{}show routing ip rip status
Routing Protocol is "rip"
  Sending updates every 30 seconds with +/-50%, next due in 22 seconds
  Timeout after 180 seconds, garbage collect after 120 seconds
  Outgoing update filter list for all interface is not set
  Incoming update filter list for all interface is not set
  Default redistribution metric is 1
  Redistributing:
  Default version control: send version 2, receive any version
    Interface        Send  Recv   Key-chain
    eth0_0           2     1 2
    No split horizon
    No authentication
    eth2_0           2     1 2
    Split horizon
    No authentication
  Routing for Networks:
    eth0_0
    eth2_0
  Routing Information Sources:
    Gateway          BadPackets BadRoutes  Distance Last Update
  Distance: (default is 120)
router{}

This status notably lists redistributed protocols, used filters, interfaces on which RIP is activated and networks that should be announced.

The most important information in this status display is the list of sending and receiving interfaces: only these interfaces receive and/or send RIP multicast announces. Other interfaces do not run RIP, for any reason (interface is down, interface has no IPv4 address, interface was not detected, interface is configured not to run RIP…).

Displaying RIPng status

The show routing ipv6 ripng status command displays a summary of RIPng protocol status. This is the first thing to do to check whether the RIPng session is OK. If RIPng protocol is not enabled, nothing will be displayed.

Example

router{}show routing ipv6 ripng status
Routing Protocol is "RIPng"
  Sending updates every 30 seconds with +/-50%, next due in 33 seconds
  Timeout after 180 seconds, garbage collect after 120 seconds
  Outgoing update filter list for all interface is not set
  Incoming update filter list for all interface is not set
  Default redistribution metric is 1
  Redistributing:
  Default version control: send version 1, receive version 1
    Interface        Send  Recv
    eth0_0           1     1
    Split horizon
    eth1_0           1     1
    Split horizon
  Routing for Networks:
    eth0_0
    eth1_0
  Routing Information Sources:
    Gateway  ReceivedPackets BadPackets  BadRoutes  Distance   Last Update
    fe80::209:c0ff:fe00:4008
                        2          0          0        120      00:00:03
    fe80::209:c0ff:fe00:400a
                        1          0          0        120      00:00:07
    fe80::202:b3ff:fec7:162c
                        1          0          0        120      00:00:07
  Distance: (default is 120)
router{}

This status notably lists redistributed protocols, used filters, interfaces on which RIPng is activated and networks that should be announced.

The most important information in this status display is the list of sending and receiving interfaces: only these interfaces receive and/or send RIPng multicast announces. Other interfaces do not run RIPng, for any reason (interface is down, interface has no IPv6 link local address, interface was not detected, interface is configured not to run RIPng…)

Displaying OSPFv2 status

The show routing ip ospf command displays a summary of OSPFv2 protocol status. This is the first thing to do to check whether the OSPFv2 session is OK. If OSPFv2 protocol is not enabled, nothing will be displayed.

router{}show routing ip ospf

Example

router{}show routing ip ospf
OSPF Routing Process, Router ID: 10.22.8.108
 Supports only single TOS (TOS0) routes
 This implementation conforms to RFC2328
 RFC1583Compatibility flag is disabled
 SPF schedule delay 1 secs, Hold time between two SPFs 1 secs
 Refresh timer 10 secs
 Redistribute Configuration
     Maximum-Prefix is not configured
 Number of external LSA 0. Checksum Sum 0x00000000
 Number of areas attached to this router: 1

 Area ID: 0 (Backbone)
   Number of interfaces in this area: Total: 1, Active: 1
   Number of fully adjacent neighbors in this area: 0
   Area has no authentication
   SPF algorithm executed 1 times
   Number of LSA 1
   Number of router LSA 1. Checksum Sum 0x00002ed2
   Number of network LSA 0. Checksum Sum 0x00000000
   Number of summary LSA 0. Checksum Sum 0x00000000
   Number of ASBR summary LSA 0. Checksum Sum 0x00000000
   Number of NSSA LSA 0. Checksum Sum 0x00000000

router{}

Additional information can be obtained with the following commands:

  • list of border routers for this area,
show routing ip ospf database
  • summary of the database (router and network link states),
show routing ip ospf neighbor
  • list of OSPFv2 neighbors.

Examples

router{}show routing ip ospf database

       OSPF Router with ID (10.22.8.108)

                Router Link States (Area 0.0.0.0)

Link State ID   ADV Router      Age  Seq#       CkSum  Link count
10.22.8.108     10.22.8.108        1 0x80000005 0xeed1 2
10.24.8.208     10.24.8.208        4 0x80000003 0xa053 2

                Net Link States (Area 0.0.0.0)

Link State ID   ADV Router      Age  Seq#       CkSum
10.23.8.208     10.24.8.208        2 0x80000001 0x10c5

                AS External Link States

Link State ID   ADV Router      Age  Seq#       CkSum  Route
10.16.0.0       10.22.8.108       48 0x80000001 0x9a75 E2 10.16.0.0/24 [0x0]
10.16.0.0       10.24.8.208       43 0x80000001 0x3079 E2 10.16.0.0/24 [0x0]
192.168.0.0     10.24.8.208       44 0x80000001 0xc198 E2 192.168.0.0/24 [0x0]

router{}show routing ip ospf neighbor

Neighbor ID     Pri   State           Dead Time   Address         Interface           RXmtL RqstL DBsmL
10.24.8.208       1   Full/DR         00:00:35    10.23.8.208     eth2_0:10.23.8.108     0
router{}

Displaying OSPFv3 status

As with OSPFv2 in IPv4, the most important commands to verify OSPFv3 status are:

show routing ipv6 ospf6 neighbor

list of OSPF neighbors,

show routing ipv6 ospf6 database

summary of the database (router and network link states).

Example

router{}show routing ipv6 ospf6 neighbor
Neighbor ID     Pri    DeadTime  State/IfState         Duration I/F[State]
10.16.0.241       1    00:00:31   Full/DR              00:00:02 eth2_0[BDR]
router{}

Note

The state field should be Full, otherwise it means that the OSPFv3 neighborhood is not correctly formed.

Displaying BGP status

To check the TCP connections of BGP for IPv4 or IPv6, use the show routing ip|ipv6 bgp summary commands.

The various displayed fields are described in the following list.

BGP router identifier

This id is used to identify the router. It is chosen as the highest Ip address configured on an interface. The router ID can be manually configured using the bgp router-id command.

local AS number
AS number of the local router.
BGP AS-PATH entries
Number of unique AS-PATH entries.
BGP community entries
Number of unique BGP community attribute combinations.
Neighbor
BGP neighbor entry in the BGP RIB.
V
BGP version number spoken to the neighbor.
AS
AS number for this neighbor.
MsgRcvd, MsgSent
Number of BGP messages received/sent from this neighbor.
TblVer
Last version of the BGP database sent to the neighbor.
InQ, OutQ
Number of messages queued to be processed or sent to the neighbor.
Up/Down
The length of time that the BGP session has been in the Established state, or the current status if not in the Established state.
State/PfxRcd
Current state of the BGP session, and the number of prefixes that have been received from a neighbor or peer group.

Examples

router{}show routing ip bgp summary
BGP router identifier 10.22.8.108, local AS number 65108
2 BGP AS-PATH entries
0 BGP community entries

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
10.23.8.208     4 65208       3       4        0    0    0 00:00:16        3

Total number of neighbors 1
router{}show routing ipv6 bgp summary
BGP router identifier 10.22.8.108, local AS number 65108
2 BGP AS-PATH entries
0 BGP community entries

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
3ffe:304:124:2308::208
                4 65208       8       8        0    0    0 00:03:40        3

Total number of neighbors 1
router{}

Displaying the forwarding tables and routing protocols tables

Displaying the IPv4 and IPv6 forwarding tables (FIBs)

The show routing ip route and show routing ipv6 route commands respectively display the IPv4 FIB (Forwarding Information Table) and IPv6 FIB, that is to say, the routes actually used by the IP stack to forward packets.

Examples

router{}show routing ip route
Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF,
       B BGP, D - DEP, > - selected route, * - FIB route

   C>* 10.16.0.0/24 is directly connected, eth1_0
C>* 10.22.4.0/24 is directly connected, eth0_0
C>* 10.23.4.0/24 is directly connected, eth2_0
R>* 10.24.4.0/24 [120/2] via 10.23.4.204, eth2_0, 00:00:27
C>* 127.0.0.0/8 is directly connected, lo0
router{}show routing ipv6 route
Codes: K - kernel route, C - connected, S - static, R - RIPng, O - OSPFv3,
       B BGP, D - DEP, N - NAT-PT, > - selected route, * - FIB route.

   C>* ::1/128 is directly connected, lo0
C>* 3ffe:304:124:2204::/64 is directly connected, eth0_0
C>* 3ffe:304:124:2304::/64 is directly connected, eth2_0
R>* 3ffe:304:124:2404::/64 [120/2] via fe80::240:33ff:fe54:b1a0, eth2_0, 00:03:11
C * fe80::/64 is directly connected, eth2_0
C * fe80::/64 is directly connected, eth0_0
C>* fe80::/64 is directly connected, lo0
router{}

Routes in the FIB originate from all activated routing protocols, network interfaces configuration and statically configured routes.

Routes displayed by the show routing ip route command are prefixed with codes that identify where the routes come from. The FIB route flag * means that this route is activated in the forwarding table. The selected route flag > means that this route may be redistributed to other routing protocols. Routes without one of these two flags are not activated in the forwarding table.

Options may be added to the show routing ip route command, to display a subset of the IPv4 FIB:

bgp
Routes learnt by BGP
connected
Directly connected routes
dep
Routes acquired by prefix delegation
kernel
Routes added by advanced external modules
ospf
Routes acquired by OSPFv2 protocol
rip
Routes acquired by RIP
static
Static routes
A.B.C.D
A specific route to a host
A.B.C.D/M
a specific route to a network

supernets-only

class-based IPv4 routes

Options may be added to show routing ipv6 route command, to display a subset of the IPv6 FIB:

bgp
Routes learnt by BGP
connected
Directly connected routes
dep
Routes acquired by prefix delegation
kernel
Routes added by advanced external modules
natpt
Routes added by the NAT-PT function
ospf6
Routes acquired by OSPFv3 protocol
ripng
Routes acquired by RIPng
static
Static routes
X:X::X:X
A specific route to a host
X:X::X:X/M
A specific route to a network

Displaying the RIP routing table (RIP RIB)

The RIP RIB (Routing Information Base) holds IPv4 routes learnt by the RIP protocol.

These routes are reported to the IPv4 FIB, which builds a forwarding table by choosing among routes gathered from all routing protocols.

The RIP RIB can be dumped by using the show routing ip rip command.

Example

router{}show routing ip rip
Codes: R - RIP, C - connected, S - Static, O - OSPF, B - BGP
       D - DEP
Sub-codes:
      (n) - normal, (s) - static, (d) - default, (r) - redistribute,
      (i) interface

        Network            Next Hop         Metric From            Tag Time
C(i) 10.22.8.0/24       0.0.0.0               1 self              0
C(i) 10.23.8.0/24       0.0.0.0               1 self              0
R(n) 10.24.8.0/24       10.23.8.208           2 10.23.8.208       0 02:58
router{}

Displaying the RIPng routing table (RIPng RIB)

The RIPng RIB (Routing Information Base) holds IPv6 routes learnt by the RIPng protocol.

These routes are reported to the IPv6 FIB, which builds a forwarding table by choosing among routes gathered from all routing protocols.

The RIPng RIB can be dumped by using the show routing ipv6 ripng command.

Example

router{}show routing ipv6 ripng
Codes: R - RIPng, C - connected, S - Static, O - OSPF, B - BGP
       D - DEP, N - NAT-PT
Sub-codes:
      (n) - normal, (s) - static, (d) - default, (r) - redistribute,
      (i) interface, (a/S) - aggregated/Suppressed

      Network      Next Hop                      Via     Metric Tag Time
C(i) 3ffe:304:124:2208::/64
                  ::                          self       1    0
C(i) 3ffe:304:124:2308::/64
                  ::                          self       1    0
R(n) 3ffe:304:124:2408::/64
                  fe80::2d0:c9ff:fe98:9353    eth2_0     2    0  02:55
router{}

Displaying the OSPFv2 routing table (OSPFv2 RIB)

The OSPFv2 RIB (Routing Information Base) holds IPv4 routes learnt by the OSPFv2 protocol.

These routes are reported to the IPv4 FIB, which builds a forwarding table by choosing among routes gathered from all routing protocols.

The OSPFv2 RIB can be dumped by using the show routing ip ospf command.

Example

router{}show routing ip ospf route
============ OSPF network routing table ============
N    10.22.8.0/24          [1] area: 0.0.0.0
                           directly attached to eth0_0
N    10.23.8.0/24          [1] area: 0.0.0.0
                           directly attached to eth2_0

============ OSPF router routing table =============

============ OSPF external routing table ===========

router{}

Displaying the OSPFv3 routing table (OSPFv3 RIB)

The OSPFv3 RIB (Routing Information Base) holds IPv6 routes learnt by the OSPFv3 protocol.

These routes are reported to the IPv6 FIB, which builds a forwarding table by choosing among routes gathered from all routing protocols.

The OSPFv3 RIB can be dumped by using the show routing ipv6 ospf6 command.

Example

router{}show routing ipv6 ospf6 route
*N IA 3ffe:304:124:2208::/64         ::                             0 00:00:20
*N IA 3ffe:304:124:2308::/64         ::                             0 00:00:20
*N IA 3ffe:304:124:2408::/64         fe80::2d0:c9ff:fe98:9353  eth2_0 00:00:15
router{}

Displaying the BGP IPv4 and IPv6 routing tables (BGP RIBs)

The BGP RIBs (Routing Information Bases) hold the IPv4 and IPv6 routes learnt by the BGP protocol.

These routes are reported to the IPv4 and IPv6 FIBs, which build a forwarding table by choosing among routes gathered from all routing protocols.

The BGP RIBs can be dumped by using the show routing ip|ipv6 bgp commands.

The various displayed fields, are described in the following list.

BGP table version
Internal version number of the table.
Local router ID
This id is used to identify the router. It is chosen as the highest IP address configured on an interface. The router ID can be manually configured using the bgp router-id command.

Status codes

s
Means the entry is suppressed.
d
Means the prefix was dampened (in case dampening is enabled).
>*
Means the entry is valid.
>
In case there are multiple entries for this prefix, > indicates the best one.
i
Means that this entry was learnt by interior BGP (in the same AS).
e
Means that this entry was learnt by exterior BGP (different AS).
?
Means that this entry was learnt through redistribution.

Origin codes

i
Means that the origin of this entry is interior BGP (in the same AS).
e
Means that the origin of this entry is exterior BGP (different AS).
?
Means that the origin of this entry is redistribution.
Network
Prefix entry in the BGP RIB.
Next Hop
Next-hop attribute advertised by BGP. In case the next-hop is 0.0.0.0, it means that this prefix is originated locally.
Metric
If shown, the value of the interautonomous system metric.
LocPrf
Local preference value (see BGP options), set to 100 by default.
Weight
Weight of the route as set via autonomous system filters.
Path
Autonomous system paths to the destination network. There can be one entry in this field for each autonomous system in the path.

Examples

router{}show routing ip bgp
BGP table version is 0, local router ID is 10.22.8.108
Status codes: s suppressed, d damped, h history,>* valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i IGP, e - EGP, ? - incomplete

      Network          Next Hop            Metric LocPrf Weight Path
*> 8.0.1.0/24       10.23.8.208              0             0 65208 i
*> 10.16.0.0/24     0.0.0.0                  0         32768 i
*> 10.22.8.0/24     0.0.0.0                  0         32768 i
*> 10.24.8.0/24     10.23.8.208              0             0 65208 i
*> 10.24.136.0/24   10.23.8.208              0             0 65208 i

Total number of prefixes 5
router{}show routing ipv6 bgp
BGP table version is 0, local router ID is 10.22.8.108
Status codes: s suppressed, d damped, h history,>* valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i IGP, e - EGP, ? - incomplete

      Network          Next Hop            Metric LocPrf Weight Path
*> 8:1::/64         3ffe:304:124:2308::208
                                             0             0 65208 i
*> 3ffe:304:124:2208::/64
                    ::                       0         32768 i
*> 3ffe:304:124:2288::/64
                    ::                       0         32768 i
*> 3ffe:304:124:2408::/64
                    3ffe:304:124:2308::208
                                             0             0 65208 i
*> 3ffe:304:124:2488::/64
                    3ffe:304:124:2308::208
                                             0             0 65208 i

Total number of prefixes 5
router{}

Displaying system usage information

To optimize the configuration of routing protocols, extensive system usage information may be displayed.

Displaying memory usage information

To display the amount of memory used, enter the following command:

router{}show routing memory

This command displays the total memory usage, including FIB manager’s library and all routing protocols. As the output of the command may be quite abundant, specific commands are provided to display focused information, as described in the following paragraphs.