High CPU Utilization Router 2801 - Interrupts

Wellington L · ‎05-04-2011

Hi,

I have problems with router 2801, the version is

Cisco IOS Software, 2801 Software (C2801-ADVENTERPRISEK9-M), Version 12.4(24)T4, RELEASE SOFTWARE (fc2)

When i start a download the processes of the router cpu stay in 99%/97%.

When i'm not doing a download the processes stay in 3%/0%.

I have one 20 mb link to Wan.

I did the troubleshooting seeing the this document :

http://www.cisco.com/en/US/products/hw/routers/ps359/products_tech_note09186a00801c2af0.shtml

But this document, isn't clear to me about how i will do to resolve this problem.

Thotsaphon Lueangwattanaphong · ‎05-04-2011

Hi,

Have you applied the following features on your router?

- Policy Based Routing. This can cause when downloading.

- Police commands (Qos). This can cause when downloading.

- Too many dynamic nat entries. This can cause when downloading.

High CPU Interrupts actually happens when process-switch getting involved. The document you provided I used to read it once. But it's not my favorite document. (grin)

HTH,

Toshi

Wellington L · ‎05-04-2011

Yes, these features have in the router.

In relationship the process switching, before this happened the IP INPUT was in 60% but i did the troubleshooting and the outside interface wasn't ip route cache habilitated.

When I habilitated this, the IP INPUT stays in 0.05% but the process in the CPU when i start the download continue in 99%/97%.

I thins is interrupt processes but i need to know about how i will do to resolve this problem.

I was thinking be the IP INPUT, but wasn't it.

I need to know too, if this router (2801) supports a 20 Mb WAN link, because before this situation i had a 12 MB WAN Link and did't have problems, and when i put 20 mb WAN Link the problems starting.

Case it is true, I need a documment to comprove this situation.

Thank You..

Wellington L · ‎05-05-2011

Only to supplement,

I read this doccument about the Router 2801, and it says about the 2801 supports 46 Mb Link no sevices enabled.

http://www.cisco.com/web/partners/downloads/765/tools/quickreference/routerperformance.pdf

But in my router i have 20 Mb Wan Link and ACL, NAT, Call Manager, VPN.....

In the processes when i start the download it goes to 99%/97%.

How will i do to resolve this problem ?

Version :

System image file is "flash:c2801-adventerprisek9-mz.124-24.T4.bin"
Cisco 2801 (revision 7.0) with 240640K/21504K bytes of memory.
Processor board ID FTX1144Y077
2 FastEthernet interfaces
31 Serial interfaces
1 Channelized/Clear E1/PRI port
1 Virtual Private Network (VPN) Module
2 Voice FXO interfaces
2 Voice FXS interfaces
6 DSPs, 96 Voice resources
DRAM configuration is 64 bits wide with parity disabled.
191K bytes of NVRAM.
127488K bytes of ATA CompactFlash (Read/Write)

CPU Processes :

CPU utilization for five seconds: 99%/97%; one minute: 91%; five minutes: 76%

2 40256 604148 66 0.39% 1.10% 0.60% 0 Load Meter

18 384696 1377668 279 0.07% 0.01% 0.00% 0 ARP Input

41 32220 3021005 10 0.07% 0.03% 0.02% 0 Per-Second Jobs

49 37796 604358 62 0.08% 0.04% 0.03% 0 Compute load avg
50 1653896 51303 32237 0.00% 0.02% 0.04% 0 Per-minute Jobs

101 77899544 21743281 3582 0.30% 0.43% 0.40% 0 IP Input

108 4607320 12685643 363 0.30% 0.41% 0.39% 0 Skinny Msg Serve

163 169636 106584017 1 0.07% 0.13% 0.19% 0 HQF Shaper Backg

108 4607320 12685643 363 0.30% 0.41% 0.39% 0 Skinny Msg Serve

149 39492 4398679 8 0.07% 0.04% 0.06% 0 CEF: IPv4 proces

163 169636 106584017 1 0.07% 0.13% 0.19% 0 HQF Shaper Backg

343 43060 1050 41009 0.89% 0.33% 0.24% 197 Virtual Exec

Interfaces :

FastEthernet0/1 is up, line protocol is up
Description: internet
Internet address is xxx.xxx.xxx/20
MTU 1500 bytes, BW 20000 Kbit/sec, DLY 100 usec,
reliability 255/255, txload 3/255, rxload 142/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:05, output 00:00:00, output hang never
Last clearing of "show interface" counters 00:46:56
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 11182000 bits/sec, 1074 packets/sec
30 second output rate 253000 bits/sec, 548 packets/sec
2916486 packets input, 3875038809 bytes
Received 546 broadcasts, 0 runts, 0 giants, 0 throttles
21 input errors, 0 CRC, 0 frame, 0 overrun, 21 ignored
0 watchdog
0 input packets with dribble condition detected
1527008 packets output, 96470325 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 unknown protocol drops
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

Thank You.

Thotsaphon Lueangwattanaphong · ‎05-05-2011

Hi,

Cisco always say that the router can do that without any service. You said that the problem occurs when downloading. Some service has to invoke CPU. Well ,11Mbps can cause the problem. Please post your configuration,excluding sensitive information.

Output queue: 0/40 (size/max)
30 second input rate 11182000 bits/sec, 1074 packets/sec
30 second output rate 253000 bits/sec, 548 packets/sec

HTH,

Toshi

Wellington L · ‎05-05-2011

Follow the configuration

Thotsaphon Lueangwattanaphong · ‎05-05-2011

Hi,

You have got many features on it. What is the mac-address applied on the rate-limit? Is the counter of this rate-limit being increased while downloading? How many nat entry when you're downloading? Just try "show ip nat statistic".

Toshi

Wellington L · ‎05-09-2011

The Mac-Address is a machine that i need to use the rate-limit, but is it the cause to do the processes up ?

The out of the nat static when I'm doing a download is this :

Total active translations: 371 (0 static, 371 dynamic; 371 extended)

Peak translations: 1477, occurred 3w1d ago

Outside interfaces:

FastEthernet0/1

Inside interfaces:

FastEthernet0/0.1, FastEthernet0/0.5, FastEthernet0/0.6, FastEthernet0/0.10

FastEthernet0/0.13, VoIP-Null0

Hits: 82566512 Misses: 0

CEF Translated packets: 38132100, CEF Punted packets: 1026623

Expired translations: 1051314

Dynamic mappings:

-- Inside Source

[Id: 8] route-map SDM_RMAP_1 interface FastEthernet0/1 refcount 364

Appl doors: 0

Normal doors: 0

Queued Packets: 0

Thank You.

Wellington L · ‎05-12-2011

I need to know if this router can use all processes like vpn, nat, call manager

and other processes with a 20 mb WAN link, becase before this situation i had a 12 mb link and never had problems with

that.

Thank You.