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BGP flapping

nany96901
Level 1
Level 1

Dear Team

 

my router gateway is my BGP neighbor

 

without the BGP configured, im able to ping my gateway with no loss of ICMP .

if BGP is configured, then if i ping to my gateway, i get packet loss.

BGP drops when packet drop.

eBGP peering establishes, then drops, re-establishes , then drops for every 20 - 30 seconds

 

what would be the issue, please suggest

 

below are the configuration details

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

interface GigabitEthernet0/0/0
 description ************GOOGLE INPUT***********
 ip address 1.1.1.1 255.255.255.252
 ip flow egress
 load-interval 30
 negotiation auto

!

router bgp XXXX
 no bgp default ipv4-unicast
 no bgp enforce-first-as
 bgp log-neighbor-changes
 bgp bestpath as-path multipath-relax
 neighbor 1.1.1.2 remote-as YYYY
 neighbor 1.1.1.2 password 7 *************************************

address-family ipv4
  no synchronization

neighbor 1.1.1.2 activate

no auto-summary
 exit-address-family

!

 

 

 

IND-INT#show interfaces gigabitEthernet 0/0/0
GigabitEthernet0/0/0 is up, line protocol is up
  Hardware is 4XGE-BUILT-IN, address is xxxxxxxxx (bia xxxxxxxxx)
  Description: ************GOOGLE INPUT***********
  Internet address is 1.1.1.1/30
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 1/255, rxload 2/255
  Encapsulation ARPA, loopback not set
  Keepalive not supported
  Full Duplex, 1000Mbps, link type is auto, media type is LX
  output flow-control is off, input flow-control is off
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:02, output 00:00:46, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 12830
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  30 second input rate 9880000 bits/sec, 1040 packets/sec
  30 second output rate 6970000 bits/sec, 4451 packets/sec
     17080544846 packets input, 22698441757070 bytes, 0 no buffer
     Received 1393 broadcasts (0 IP multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 253977 multicast, 0 pause input
     11445196608 packets output, 1842515648152 bytes, 0 underruns
     0 output errors, 0 collisions, 2 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

 

 

Regards

Narayan

 

 

1 Reply 1

Two things:

1. What the HW model you ar using ? is there any kind of high CPU after enabling BGP ? any kind of memory buffer logs ??

2. share the output of "sh log" and "sh ip route <GW-IP>" for 20-30 sec. when BGP is up and you are able to ping your GW with packet loss.

 

Vivek

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