[c-nsp] Unidirectional CDP traffic

Gökhan Gümüş ggumus at gmail.com
Thu Mar 31 07:50:33 EDT 2011 

Hi Daniel,

Thanks for this.
Actually interfaces are all working as trunk port however they configured
like this.

We cleared counters and made ping tests.
Please see our test results below,

*Clearing counters:

*
=== London ===
LIXCORML01#cle count gi3/16
Clear "show interface" counters on this interface [confirm]
LIXCORML01#p 10.119.44.150

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.119.44.150, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

LIXCORML01#sh int gi3/16
GigabitEthernet3/16 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet Port, address is 68ef.bd4f.ccd7 (bia
68ef.bd4f.ccd7)
  Description: abc
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseLH
  input flow-control is on, output flow-control is on
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output never, output hang never
  Last clearing of "show interface" counters 00:00:21
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 1000 bits/sec, 1 packets/sec
     0 packets input, 287503 bytes, 0 no buffer
     Received 0 broadcasts (0 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     38 packets output, 2720 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

LIXCORML01#sh cdp nei gi3/16
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone,
                  D - Remote, C - CVTA, M - Two-port Mac Relay

Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID
LIXCORML01#
===

=== Stockholm ===

SOXCORML01#cle count gi3/11
Clear "show interface" counters on this interface [confirm]
SOXCORML01#p 10.119.44.149

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.119.44.149, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

SOXCORML01#sh int gi3/11
GigabitEthernet3/11 is up, line protocol is up (connected)
  Hardware is Gigabit Ethernet Port, address is 68ef.bd4f.c51e (bia
68ef.bd4f.c51e)
  Description: abc
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseLH
  input flow-control is on, output flow-control is on
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output never, output hang never
  Last clearing of "show interface" counters 00:00:21
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 0 bits/sec, 0 packets/sec
  5 minute output rate 0 bits/sec, 0 packets/sec
     35 packets input, 2910 bytes, 0 no buffer
     Received 35 broadcasts (35 multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 input packets with dribble condition detected
     53 packets output, 3776 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier
     0 output buffer failures, 0 output buffers swapped out

SOXCORML01#sh cdp nei gi3/11
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone,
                  D - Remote, C - CVTA, M - Two-port Mac Relay

Device ID        Local Intrfce     Holdtme    Capability  Platform  Port ID
LIXCORML01.nd.barcapint.com <http://lixcorml01.nd.barcapint.com/>
                 Gig 3/11          133             R S I  WS-C4900M Gig 3/16
SOXCORML01#
===

Thanks in advance.

Gokhan

2011/3/31 Daniel Dib <daniel.dib at reaper.nu>

> On to, mar 31, 2011 at 13:22:19, Gökhan Gümüş wrote:
> > Subject: [c-nsp] Unidirectional CDP traffic
> >
> > Hi all,
> >
> > One of our customer is experiencing a strange problem.
> > We are providing a link between London and Stockholm via DWDM.
> > Customer is not able to ping remote site.
> > Strange things from Stockholm he can see London site as CDP neighbor.
> > From London he can not...
> > Configs are below;
> >
> > === London ===
> > LIXCORML01#cle count gi3/16
> > Clear "show interface" counters on this interface [confirm]
> > LIXCORML01#p 10.119.44.150
> >
> > Type escape sequence to abort.
> > Sending 5, 100-byte ICMP Echos to 10.119.44.150, timeout is 2 seconds:
> > .....
> > Success rate is 0 percent (0/5)
> >
> > -----Stockholm----
> >
> > SOXCORML01#sh cdp nei gi3/11
> > Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
> >                   S - Switch, H - Host, I - IGMP, r - Repeater, P -
> > Phone,
> >                   D - Remote, C - CVTA, M - Two-port Mac Relay
> >
> > Device ID        Local Intrfce     Holdtme    Capability  Platform
> > Port ID
> > LIXCORML01.abc <http://lixcorml01.nd.barcapint.com/>
> >                  Gig 3/11          133             R S I  WS-C4900M Gig
> > 3/16
> > SOXCORML01#
> >
> > Interface configs are below;
> >
> > === London ===
> > interface GigabitEthernet3/16
> >  description euNetworks BAR0001_LON_STO_GE_26254_001 to SOXCORML01
> > Gi3/11  switchport access vlan 628  switchport trunk native vlan 628
> > switchport trunk allowed vlan 628,728  switchport mode trunk  speed
> > nonegotiate end === === Stockholm === interface GigabitEthernet3/11
> > description euNetworks BAR0001_LON_STO_GE_26254_001 to LIXCORML01
> > Gi3/16  switchport access vlan 628  switchport trunk native vlan 628
> > switchport trunk allowed vlan 628,728  switchport mode trunk  speed
> > nonegotiate  spanning-tree portfast end
> >
> > === London ===
> > LIXCORML01#sh int gi3/16 sw
> > Name: Gi3/16
> > Switchport: Enabled
> > Administrative Mode: trunk
> > Operational Mode: trunk
> > Administrative Trunking Encapsulation: dot1q Operational Trunking
> > Encapsulation: dot1q Negotiation of Trunking: On Access Mode VLAN: 628
> > (628-SOX-PROD) Trunking Native Mode VLAN: 628 (628-SOX-PROD)
> > Administrative Native VLAN tagging: enabled Voice VLAN: none
> > Administrative private-vlan host-association: none Administrative
> > private-vlan mapping: none Administrative private-vlan trunk native
> > VLAN: none Administrative private-vlan trunk Native VLAN tagging:
> > enabled Administrative private-vlan trunk encapsulation: dot1q
> > Administrative private-vlan trunk normal VLANs: none Administrative
> > private-vlan trunk associations: none Administrative private-vlan
> > trunk
> > mappings: none Operational private-vlan: none Trunking VLANs Enabled:
> > 628,728 Pruning VLANs Enabled: 2-1001 Capture Mode Disabled Capture
> > VLANs Allowed: ALL
> >
> > Unknown unicast blocked: disabled
> > Unknown multicast blocked: disabled
> > Appliance trust: none
> > ===
> > === Stockholm ===
> > SOXCORML01#sh int gi3/11 sw
> > Name: Gi3/11
> > Switchport: Enabled
> > Administrative Mode: trunk
> > Operational Mode: trunk
> > Administrative Trunking Encapsulation: dot1q Operational Trunking
> > Encapsulation: dot1q Negotiation of Trunking: On Access Mode VLAN: 628
> > (628-LIX-PROD) Trunking Native Mode VLAN: 628 (628-LIX-PROD)
> > Administrative Native VLAN tagging: enabled Voice VLAN: none
> > Administrative private-vlan host-association: none Administrative
> > private-vlan mapping: none Administrative private-vlan trunk native
> > VLAN: none Administrative private-vlan trunk Native VLAN tagging:
> > enabled Administrative private-vlan trunk encapsulation: dot1q
> > Administrative private-vlan trunk normal VLANs: none Administrative
> > private-vlan trunk associations: none Administrative private-vlan
> > trunk
> > mappings: none Operational private-vlan: none Trunking VLANs Enabled:
> > 628,728 Pruning VLANs Enabled: 2-1001 Capture Mode Disabled Capture
> > VLANs Allowed: ALL
> >
> > Unknown unicast blocked: disabled
> > Unknown multicast blocked: disabled
> > Appliance trust: none
> > SOXCORML01#
> > ===
> >
> > Anybody had such an experience before?
> >
> > Thanks and regards,
> > Gokhan Gumus
> > _______________________________________________
> > cisco-nsp mailing list  cisco-nsp at puck.nether.net
> > https://puck.nether.net/mailman/listinfo/cisco-nsp
> > archive at http://puck.nether.net/pipermail/cisco-nsp/
>
> If he can see London from STHLM that would imply that TX from London and RX
> in STHLM is working as expected. The issue should be with LONDON RX and
> STHLM TX. On the London port you have both the port configured as access
> and
> as a trunk, that can cause weird things. Is this the same in STHLM also?
> You
> are using speed nonegotiate which shouldn't cause issues like this but it's
> better to have auto enabled unless you absolutely cannot get the link
> stable
> with it. What about the counters for the interfaces in LONDON and STHLM,
> are
> they increasing? And are they increasing both inbound and outbound?
>
> /Daniel
>
>

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