Re: OSPF Agency not Establish after link flapping - Page 2

abdulhakam · ‎08-08-2025

HI,

Any one can assist me, i noticed some of the segment OSPF neighboard became INIT, We have 2 CS which run on HSRP.

MKLDC-10-6509-1#show standby brief
P indicates configured to preempt.
|
Interface Grp Prio P State Active addr Standby addr Group addr
Vl1 1 110 P Active local unknown 10.200.1.1
Vl20 20 110 P Active local 10.200.20.6 10.200.20.1
Vl21 21 110 P Active local 10.200.21.6 10.200.21.1
Vl100 100 110 P Active local unknown 10.200.100.7
Vl102 102 110 P Active local unknown 10.200.102.3
Vl103 103 110 P Active local unknown 10.200.103.1
Vl104 104 100 P Standby 10.200.104.3 local 10.200.104.1
Vl110 110 110 P Active local 10.200.110.3 10.200.110.1
Vl214 214 110 P Active local 10.200.214.6 10.200.214.1
Vl218 218 110 P Active local 10.200.218.6 10.200.218.1
Vl239 239 110 P Active local unknown 10.200.239.1
Vl240 240 110 P Active local 10.200.240.6 10.200.240.1
MKLDC-10-6509-1#

MKLDC-10-6509-1#show ip ospf neighbor

Neighbor ID Pri State Dead Time Address Interface
10.10.10.2 1 INIT/DROTHER 00:00:36 10.200.214.6 Vlan214
10.10.10.2 1 INIT/DROTHER 00:00:33 10.200.218.6 Vlan218
10.10.10.2 1 INIT/DROTHER 00:00:33 10.200.240.6 Vlan240
10.10.10.2 1 FULL/DR 00:00:33 10.200.101.6 Vlan101
10.10.10.2 1 FULL/DR 00:00:33 10.200.100.6 Vlan100
10.10.10.9 1 FULL/DROTHER 00:00:30 10.200.100.10 Vlan100
10.10.10.17 0 FULL/DROTHER 00:00:31 10.200.100.26 Vlan100
10.10.10.18 0 FULL/DROTHER 00:00:37 10.200.100.27 Vlan100
10.10.10.2 1 INIT/DROTHER 00:00:30 10.200.21.6 Vlan21
10.10.10.2 1 INIT/DROTHER 00:00:32 10.200.20.6 Vlan20
10.10.10.2 1 FULL/DR 00:00:33 10.200.1.6 Vlan1
10.10.10.14 0 FULL/ - 00:00:36 10.199.100.10 GigabitEthernet5/2
10.10.10.11 0 FULL/ - 00:00:39 10.199.100.2 GigabitEthernet3/3
MKLDC-10-6509-1#
MKLDC-10-6509-1#

Anyone can assit, dont know where to check.

abdulhakam · ‎08-08-2025

So its safe if we can remove that config ? is non disruptive right ?

MHM Cisco World · ‎08-08-2025

remove what friend ? QoS
show interface x/x <<- check the output drop
show policy-map interface <interface> check the queue depth and drop

MHM

abdulhakam · ‎08-08-2025

interface GigabitEthernet4/1
description **EtherChannel to MKLDC-10-6509-2 via Gi4/1**
switchport
switchport trunk encapsulation dot1q
switchport mode trunk
no ip address
priority-queue cos-map 1 5 6 7 ------> This line
channel-group 1 mode desirable
!
interface GigabitEthernet4/2
description **EtherChannel to MKLDC-10-6509-2 via Gi4/2**
switchport
switchport trunk encapsulation dot1q
switchport mode trunk
no ip address
priority-queue cos-map 1 5 6 7 ---- > This line
channel-group 1 mode desirable
!
interface GigabitEthernet4/3

MHM Cisco World · ‎08-08-2025

I edit my comment check it

MHM

abdulhakam · ‎08-08-2025

Hi,

MKLDC-10-6509-1#show policy-map interface gigabitEthernet 4/1
MKLDC-10-6509-1#show policy-map interface gigabitEthernet 4/2

-- No Output form command above--

For interface drop :

MKLDC-10-6509-1#show interface gigabitEthernet 4/1
GigabitEthernet4/1 is up, line protocol is up (connected)
Hardware is C6k 1000Mb 802.3, address is 0016.9d19.42c4 (bia 0016.9d19.42c4)
Description: **EtherChannel to MKLDC-10-6509-2 via Gi4/1**
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 4/255, rxload 4/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s
input flow-control is off, output flow-control is off
Clock mode is auto
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:52, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/944/0 (size/max/drops/flushes); Total output drops: 4664321
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 19170000 bits/sec, 3271 packets/sec
5 minute output rate 19214000 bits/sec, 3185 packets/sec
3662397839079 packets input, 858823363889522 bytes, 0 no buffer
Received 1718733080 broadcasts (1249386531 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 472 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
3652124992921 packets output, 735218244379251 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
MKLDC-10-6509-1#show interface gigabitEthernet 4/2
GigabitEthernet4/2 is up, line protocol is up (connected)
Hardware is C6k 1000Mb 802.3, address is 0016.9d19.42c5 (bia 0016.9d19.42c5)
Description: **EtherChannel to MKLDC-10-6509-2 via Gi4/2**
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s
input flow-control is off, output flow-control is off
Clock mode is auto
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:40, output 00:00:57, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/1860/0 (size/max/drops/flushes); Total output drops: 12805208
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 13555000 bits/sec, 2592 packets/sec
5 minute output rate 5015000 bits/sec, 1412 packets/sec
759750920411 packets input, 659778981140477 bytes, 0 no buffer
Received 3589773904 broadcasts (353657531 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 930 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
696280687997 packets output, 482634923390135 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
MKLDC-10-6509-1#

---- the value not increasing----

MHM Cisco World · ‎08-08-2025

value of output drop not increase after 5 min ?
MHM

MHM Cisco World · ‎08-08-2025

you use PO between two SW ?
if Yes then

show port channel summary <<- in both SW
also run this again

MKLDC-10-6509-1#show policy-map interface <PO> <<- this need

MHM

abdulhakam · ‎08-08-2025

I run again now (afterb 11m), interface 4/1 got increament by 1. interface 4/2 remain same.

----show port channel summary----

MKLDC-10-6509-1#show interfaces port-channel 1 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
-------------------------------------------------------------------------
* Port-channel1 0 17051 0 58896661 554088000 147314 173378000 181900 0
NOTE:No separate counters are maintained for subinterfaces
Hence Details of subinterface are not shown
MKLDC-10-6509-1#

MKLDC-10-6509-2#show interfaces port-channel 1 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
-------------------------------------------------------------------------
* Port-channel1 0 363 0 1932799900 168038000 180942 549477000 147227 0
NOTE:No separate counters are maintained for subinterfaces
Hence Details of subinterface are not shown
MKLDC-10-6509-2#

--------------------------------------------------------------------------

MKLDC-10-6509-1#show policy-map interface port-channel 1
MKLDC-10-6509-1#

run at both switch not output, also no output

MHM Cisco World · ‎08-08-2025

show port-channel summary OR show etherchannel summary
not show interface port-channel summary
you do nice mistake run above command which show us there are drop in queue

* Port-channel1 0 17051 0 58896661 554088000 147314 173378000 181900 0

* Port-channel1 0 363 0 1932799900 168038000 180942 549477000 147227 0

abdulhakam · ‎08-08-2025

Haha, because no command for show port-channel,

------------------------------------------------------------------------------------

MKLDC-10-6509-1#show etherchannel summary
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use f - failed to allocate aggregator

M - not in use, minimum links not met
u - unsuitable for bundling
w - waiting to be aggregated
Number of channel-groups in use: 4
Number of aggregators: 4

Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
1 Po1(SU) PAgP Gi3/1(P) Gi3/2(P) Gi4/1(P) Gi4/2(P)
8 Po8(SD) LACP Gi3/22(I) Gi3/26(I)
33 Po33(SU) LACP Gi3/14(P) Gi3/15(P) Gi3/16(P)
271 Po271(SD) -

MKLDC-10-6509-1#

------------------------------------------------------------------------

MKLDC-10-6509-2#show etherchannel summary
Flags: D - down P - bundled in port-channel
I - stand-alone s - suspended
H - Hot-standby (LACP only)
R - Layer3 S - Layer2
U - in use f - failed to allocate aggregator

M - not in use, minimum links not met
u - unsuitable for bundling
w - waiting to be aggregated
Number of channel-groups in use: 5
Number of aggregators: 5

Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
1 Po1(SU) PAgP Gi3/1(P) Gi3/2(P) Gi4/1(P) Gi4/2(P)
8 Po8(SU) LACP Gi3/13(P) Gi4/3(P)
11 Po11(SU) LACP Gi3/6(P) Gi7/6(P)
33 Po33(SU) LACP Gi3/14(P) Gi3/15(P) Gi3/16(P)
271 Po271(SD) -

MKLDC-10-6509-2#

MHM Cisco World · ‎08-08-2025

1 Po1(SU) PAgP Gi3/1(P) Gi3/2(P) Gi4/1(P) Gi4/2(P)
8 Po8(SD) LACP Gi3/22(I) Gi3/26(I)
33 Po33(SU) LACP Gi3/14(P) Gi3/15(P) Gi3/16(P)
271 Po271(SD) -

1 Po1(SU) PAgP Gi3/1(P) Gi3/2(P) Gi4/1(P) Gi4/2(P)
8 Po8(SU) LACP Gi3/13(P) Gi4/3(P)
11 Po11(SU) LACP Gi3/6(P) Gi7/6(P)
33 Po33(SU) LACP Gi3/14(P) Gi3/15(P) Gi3/16(P)

the PO1 is SU and all port member is P and run PAgP.
so only think is Queue drop the packet in PO
QoS can be issue but as you mention this config work before and no change in config ?
QoS will effect PO in case that PO UP/DOWN recently,

let me check the effect of apply QoS in some port member and not all

thanks

MHM

abdulhakam · ‎08-08-2025

Yes, no config change and its working before, we notice this happen after flapping happeb at one of the interface in Po1 which is Gig3/1

MHM Cisco World · ‎08-08-2025

sure QoS must config same in all port
So you need to shut port then remove QoS <<- I am with this solution
OR
shut/no shut the PO

MHM

abdulhakam · ‎08-08-2025

Hi MHM,

Thank you for you suggestion and respond, will disucss this with team since shut the Po will have impact to our current production traffic, but i now sure if shut the specific port. Previously we already remove the Qos but nothing happen and we re add back the config.

Thank You Again.

MHM Cisco World · ‎08-08-2025

Take your time friend

Remember debug command to check after do step needed

Goodluck

MHM