ASR1002-HX (16GB RAM) BGP flaps

[walker333]

Hello all,

I have a very strange problem with an ASR1002-HX. This is my secondary router (my primary is an ASR9901). The two routers are directly connected and each one is connected to the same provider with a 10G ethernet. The internal routing protocol is ospf and the external (with the provider) is BGP. The two routers are also running iBGP between them. I'm using both IPv4 and IPv6.

The problem is that the IPv4 eBGP (with the provider) which is running on the ASR1002-HX is flapping every few hours with no apparent reason. The IPv6 has no problem. I tried moving the peering to my primary router (ASR9901) and it is running without any problem. I also tried moving the ASR9901 bgp peering to the ASR1002-HX and it is also flapping every few hours. The iBGP between my two routers is steady and has no problem. The router has plenty of RAM (16GB) and the bgp is receiving only the default route. There is also another eBGP, which receives only one route. This peering is steady.

Unfortunately I have no support from Cisco for the time being and I don't know what to do. It seems to me like a bug. Do you have any ideas to suggest? The IOS of my router is 17.09.04 and the provider's router is a Juniper.

[Georg Pauwen]

Hello,

since you only receive the default route from your ISP, memory or resources cannot be the problem. Do the logs of the ASR give any indication of what is causing the flaps ?

[Richard Burts]

Have you asked the provider if they are aware of any issues on their side?

[Leo Laohoo]

So "anything" on the ASR 1002-HX is flapping is it? 

What firmware is the router on? 
What is the uptime of the router? 
Post the complete output to the following commands: 

sh platform resources
sh platform software status con brief

[walker333]

The logs don't show any clue. Wireshark sniff of the traffic doesn't show anything wrong. The IOS version is 17.09.04 and the output of the commands is

warp#sh platform resources
**State Acronym: H - Healthy, W - Warning, C - Critical
Resource Usage Max Warning Critical State
----------------------------------------------------------------------------------------------------
RP0 (ok, active) H
Control Processor 5.00% 100% 80% 90% H
DRAM 4716MB(29%) 15792MB 88% 93% H
bootflash 1512MB(5%) 26686MB 88% 93% H
harddisk 0MB(0%) 0MB 88% 93% H
ESP0(ok, active) H
QFP H
TCAM 5718cells(0%) 1048576cells 65% 85% H
DRAM 400704KB(9%) 4194304KB 85% 95% H
IRAM 14038KB(10%) 131072KB 85% 95% H
CPU Utilization 1.00% 100% 90% 95% H
Crypto Utilization 0.00% 100% 90% 95% H
Pkt Buf Mem (0) 67KB(0%) 524288KB 85% 95% H
Pkt Buf Mem (1) 67KB(0%) 524288KB 85% 95% H

warp#sh platform software status con brief
Load Average
Slot Status 1-Min 5-Min 15-Min
RP0 Healthy 0.37 0.34 0.38

Memory (kB)
Slot Status Total Used (Pct) Free (Pct) Committed (Pct)
RP0 Healthy 16171120 4830856 (30%) 11340264 (70%) 10528176 (65%)

CPU Utilization
Slot CPU User System Nice Idle IRQ SIRQ IOwait
RP0 0 7.09 10.58 0.00 81.21 0.00 1.09 0.00
1 0.40 0.60 0.00 99.00 0.00 0.00 0.00
2 4.80 2.40 0.00 92.70 0.00 0.10 0.00
3 1.10 1.10 0.00 97.80 0.00 0.00 0.00
4 3.80 5.30 0.00 90.90 0.00 0.00 0.00
5 2.79 2.19 0.00 95.00 0.00 0.00 0.00
6 7.50 1.10 0.00 91.40 0.00 0.00 0.00
7 2.50 0.60 0.00 96.89 0.00 0.00 0.00

warp#

[Leo Laohoo]

---

@walker333 wrote:
The IOS version is 17.09.04

---

Off-Topic:  Is HTTP/HTTPS enabled in this router?

[Giuseppe Larosa]

Hello @walker333 ,

>> The problem is that the IPv4 eBGP (with the provider) which is running on the ASR1002-HX is flapping every few hours with no apparent reason.

check the logs in the router looking for lines that include the eBGP peer address

show log | inc <eBGP-peer-IP-address>

either you receive a BGP notification from the peer or you see the BGP hold timer that expires.

Edit:

Also check the capabilities exchanged with the eBGP neighbor using

show ip bgp neighbor <eBGP-peer-IP-address>

Being  a Juniper on the other side pay attention to the route refresh capability.

it is advertised and received or only received ?

Hope to help

Giuseppe

[MHM Cisco World]

Can i see 

Show ip bgp 

MHM

[walker333]

Thank you all for your answers. I gave up and I moved the bgp peering to a third router. Now it is working perfectly. I believe that there is an IOS bug but without an active support contract I cannot prove it.

[Richard Burts · Accepted solution]

Thanks for the update. Glad that now it is working perfectly. Sorry that we were not able to help you find a solution.