Cisco interfaces not showing when doing 'show ip interface brief'

[Dam_Karp]

Hi, I trust you are well.

I and battling to find the rest of the interfaces on my Cisco 800 Series (837) router when I'm typing the 'show ip interface brief' command. The router has 4 Ethernet Ports, yet I only see Ethernet0. I still only see Ethernet0 with the 'show running-config' command.

Also, I assigned an IP address for that Ethernet0 interface and created a bunch of Loopback interfaces to have extra networks. I then made use of EIGRP as my routing protocol to advertise the Loopback interfaces. When I disconnect the Ethernet cable (from port 1) and plug it back in (into port 2, 3 or 4), then EIGRP simply re-synchronizes and the paths to the Loopback interfaces are once again present in the routing tables of the other neighboring routers.

IOS version: 12.3(2)XA5

IOS: c837-k9o3sy6-mz.123-2.XA5.bin

Any suggestions will be appreciated.

Thank You,
Dam_Karp

[Seb Rupik]

Hi there,

That sounds a little odd.

With the cable connected to one of the ports 2,3,4 and with the EIGRP adjacency having formed, what is the output of:

show ip eigrp interfaces

Can you share the entire running config?

cheers,

Seb.

[Dam_Karp]

EIGRP:

STAND_ALONE_ROUTER#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route

Gateway of last resort is not set

1.0.0.0/32 is subnetted, 1 subnets
D 1.1.1.1 [90/412160] via 10.1.30.2, 00:00:40, Ethernet0
2.0.0.0/32 is subnetted, 1 subnets
D 2.2.2.2 [90/409600] via 10.1.30.2, 00:04:23, Ethernet0
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
D 10.1.10.0/24 [90/284160] via 10.1.30.2, 00:01:12, Ethernet0
C 10.2.1.1/32 is directly connected, Loopback2
C 10.3.1.1/32 is directly connected, Loopback3
C 10.1.1.1/32 is directly connected, Loopback1
C 10.4.1.1/32 is directly connected, Loopback4
C 10.1.30.0/24 is directly connected, Ethernet0

*Mar 1 00:15:34.363: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).

INTERFACES
STAND_ALONE_ROUTER#show ip int br
Interface IP-Address OK? Method Status Protocol
ATM0 unassigned YES TFTP administratively down down
Ethernet0 10.1.30.1 YES TFTP up up
Ethernet0.100 unassigned YES unset up up
Loopback1 10.1.1.1 YES TFTP up up
Loopback2 10.2.1.1 YES TFTP up up
Loopback3 10.3.1.1 YES TFTP up up
Loopback4 10.4.1.1 YES TFTP up up

RUNNING-CONFIG
STAND_ALONE_ROUTER#show run
Building configuration...

Current configuration : 1048 bytes
!
version 12.3
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname STAND_ALONE_ROUTER
!
memory-size iomem 5
enable password cisco
!
no aaa new-model
ip subnet-zero
!
!
ip audit notify log
ip audit po max-events 100
no ftp-server write-enable
!
!
!
!
!
!
!
interface Loopback1
ip address 10.1.1.1 255.255.255.255
!
interface Loopback2
ip address 10.2.1.1 255.255.255.255
!
interface Loopback3
ip address 10.3.1.1 255.255.255.255
!
interface Loopback4
ip address 10.4.1.1 255.255.255.255
!
interface Ethernet0
ip address 10.1.30.1 255.255.255.0
hold-queue 100 out
!
interface Ethernet0.100
!
interface ATM0
no ip address
shutdown
no atm ilmi-keepalive
dsl operating-mode auto
!
router eigrp 1
network 10.0.0.0
no auto-summary
!
ip classless
no ip http server
no ip http secure-server
!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
no modem enable
line aux 0
line vty 0 4
password cisco
login
!
scheduler max-task-time 5000
!
end

I MADE SOME OF THE CONFIGS SIMPLE (E.G. PASSWORDS, BECAUSE IT'S LAB ROUTERS)

AT THIS POINT IN TIME, I SWITCHED THE CABLE FROM PORT 2 TO PORT 1 (ETHERNET) AND THE SYSLOGS ARE AS FOLLOWS:

STAND_ALONE_ROUTER#
*Mar 1 00:16:29.991: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).
STAND_ALONE_ROUTER#
*Mar 1 00:16:31.779: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).
*Mar 1 00:16:32.779: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).
STAND_ALONE_ROUTER#
*Mar 1 00:16:37.799: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 10.1.30.2 (Ethernet0) is down: holding time expired
STAND_ALONE_ROUTER#
*Mar 1 00:16:59.783: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 10.1.30.2 (Ethernet0) is up: new adjacency

AFTER THE CHANGE:

STAND_ALONE_ROUTER#show run | s interface
interface Loopback1
ip address 10.1.1.1 255.255.255.255
interface Loopback2
ip address 10.2.1.1 255.255.255.255
interface Loopback3
ip address 10.3.1.1 255.255.255.255
interface Loopback4
ip address 10.4.1.1 255.255.255.255
interface Ethernet0
ip address 10.1.30.1 255.255.255.0
hold-queue 100 out
interface Ethernet0.100
interface ATM0
no ip address
shutdown
no atm ilmi-keepalive
dsl operating-mode auto

[Seb Rupik]

I've never played with a 837 and having read the datasheet, it looks like the fa0-3 ports are Layer2 only, and oddly it looks like they are all members of VLAN1 (ethernet0). This explains why you can move the RJ45 cable between the fa0-3 ports and keep on forming EIGRP adjacencies.

Apparently you should be able to configure the duplex settings on the Fa ports which implies they should show in the running config.

What is the output for sh run all

cheers,

Seb.

[Dam_Karp]

Hi, 

The show run all command doesn't seem to be working on this version of the IOS. However, I typed "show run full"; this is my config:

STAND_ALONE_ROUTER#show run ?
brief configuration without certificate data
class-map Show class-map information
full full configuration
interface Show interface configuration
linenum Display line numbers in output
map-class Show map class information
policy-map Show policy-map information
vc-class Show vc class information
| Output modifiers
<cr>

STAND_ALONE_ROUTER#show run full
Building configuration...

Current configuration : 1048 bytes
!
version 12.3
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname STAND_ALONE_ROUTER
!
memory-size iomem 5
enable password cisco
!
no aaa new-model
ip subnet-zero
!
!
ip audit notify log
ip audit po max-events 100
no ftp-server write-enable
!
!
!
!
!
!
!
interface Loopback1
ip address 10.1.1.1 255.255.255.255
!
interface Loopback2
ip address 10.2.1.1 255.255.255.255
!
interface Loopback3
ip address 10.3.1.1 255.255.255.255
!
interface Loopback4
ip address 10.4.1.1 255.255.255.255
!
interface Ethernet0
ip address 10.1.30.1 255.255.255.0
hold-queue 100 out
!
interface Ethernet0.100
!
interface ATM0
no ip address
shutdown
no atm ilmi-keepalive
dsl operating-mode auto
!
router eigrp 1
network 10.0.0.0
no auto-summary
!
ip classless
no ip http server
no ip http secure-server
!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
no modem enable
line aux 0
line vty 0 4
password cisco
login
!
scheduler max-task-time 5000
!
end

Please let me know if you need something. 

Thank You, 

Dam_Karp.

[Seb Rupik]

Since the Fa's are layer2 only, do they appear with the command:

sh int status

cheers,

Seb.

[Dam_Karp]

The show interface status command doesn't work as well. I did a lot of other commands, I hope this helps:

STAND_ALONE_ROUTER#show interfaces ?
ATM ATM interface
Async Async interface
BVI Bridge-Group Virtual Interface
CTunnel CTunnel interface
Dialer Dialer interface
Ethernet IEEE 802.3
Loopback Loopback interface
MFR Multilink Frame Relay bundle interface
Multilink Multilink-group interface
Null Null interface
Tunnel Tunnel interface
Vif PGM Multicast Host interface
Virtual-PPP Virtual PPP interface
Virtual-Template Virtual Template interface
Virtual-TokenRing Virtual TokenRing
accounting Show interface accounting
crb Show interface routing/bridging info
dampening Show interface dampening info
description Show interface description
irb Show interface routing/bridging info
mac-accounting Show interface MAC accounting info
mpls-exp Show interface MPLS experimental accounting info
precedence Show interface precedence accounting info
rate-limit Show interface rate-limit info
stats Show interface packets & octets, in & out, by switching
path
summary Show interface summary
switching Show interface switching
| Output modifiers
<cr>

*Mar 1 00:10:33.347: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).

STAND_ALONE_ROUTER#show interfaces des
Interface Status Protocol Description
AT0 admin down down
Et0 up up
Et0.100 up up
Lo1 up up
Lo2 up up
Lo3 up up
Lo4 up up

STAND_ALONE_ROUTER#show interfaces stats
Interface ATM0 is disabled

Ethernet0
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 73 6502 133 14064
Route cache 0 0 0 0
Total 73 6502 133 14064
Loopback1
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 64 3840
Route cache 0 0 0 0
Total 0 0 64 3840
Loopback2
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 64 3840
Route cache 0 0 0 0
Total 0 0 64 3840
Loopback3
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 64 3840
Route cache 0 0 0 0
Total 0 0 64 3840
Loopback4
Switching path Pkts In Chars In Pkts Out Chars Out
Processor 0 0 64 3840
Route cache 0 0 0 0
Total 0 0 64 3840

STAND_ALONE_ROUTER#show interfaces summary

*: interface is up
IHQ: pkts in input hold queue IQD: pkts dropped from input queue
OHQ: pkts in output hold queue OQD: pkts dropped from output queue
RXBS: rx rate (bits/sec) RXPS: rx rate (pkts/sec)
TXBS: tx rate (bits/sec) TXPS: tx rate (pkts/sec)
TRTL: throttle count

Interface IHQ IQD OHQ OQD RXBS RXPS TXBS TXPS TRTL
------------------------------------------------------------------------
ATM0 0 0 0 0 0 0 0 0 0
* Ethernet0 0 0 0 0 0 0 0 0 0
* Ethernet0.100 - - - - - - - - -
* Loopback1 0 0 0 0 0 0 0 0 0
* Loopback2 0 0 0 0 0 0 0 0 0
* Loopback3 0 0 0 0 0 0 0 0 0
* Loopback4 0 0 0 0 0 0 0 0 0
NOTE:No separate counters are maintained for subinterfaces
Hence Details of subinterface are not shown

*Mar 1 00:11:33.331: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0 (not full duplex), with WIFI_ROUTER FastEthernet3 (full duplex).

STAND_ALONE_ROUTER#show interfaces switching
Interface ATM0 is disabled

Ethernet0
Throttle count 0
Drops RP 0 SP 0
SPD Flushes Fast 0 SSE 0
SPD Aggress Fast 0
SPD Priority Inputs 82 Drops 0

Protocol Path Pkts In Chars In Pkts Out Chars Out
Other Process 0 0 60 3600
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
IP Process 82 6054 78 5934
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
ARP Process 1 60 1 60
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
CDP Process 5 1780 16 6704
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
Loopback1
Throttle count 0
Drops RP 0 SP 0
SPD Flushes Fast 0 SSE 0
SPD Aggress Fast 0
SPD Priority Inputs 0 Drops 0

Protocol Path Pkts In Chars In Pkts Out Chars Out
IP Process 77 4620 77 4620
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
Loopback2
Throttle count 0
Drops RP 0 SP 0
SPD Flushes Fast 0 SSE 0
SPD Aggress Fast 0
SPD Priority Inputs 0 Drops 0

Protocol Path Pkts In Chars In Pkts Out Chars Out
IP Process 78 4680 78 4680
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
Loopback3
Throttle count 0
Drops RP 0 SP 0
SPD Flushes Fast 0 SSE 0
SPD Aggress Fast 0
SPD Priority Inputs 0 Drops 0

Protocol Path Pkts In Chars In Pkts Out Chars Out
IP Process 78 4680 78 4680
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0
Loopback4
Throttle count 0
Drops RP 0 SP 0
SPD Flushes Fast 0 SSE 0
SPD Aggress Fast 0
SPD Priority Inputs 0 Drops 0

Protocol Path Pkts In Chars In Pkts Out Chars Out
IP Process 78 4680 78 4680
Cache misses 0
Fast 0 0 0 0
Auton/SSE 0 0 0 0

[Seb Rupik · Accepted solution]

Thanks for sharing the output, the Fa interfaces are well hidden!!

Certainly them not showing up with the sh ip int br is down to them being Layer2 interfaces. 

The 837 was a fairly cheap (for cisco) SOHO router so this may explain why it doesn't behave like a normal IOS device.

cheers,

Seb.