09-10-2011 08:12 AM - edited 03-07-2019 02:08 AM
Hello,
We are thinking of replacing our router 2811 with a newer model 2911 dude to high CPU utilizaiton. Can anyone please give us a comparison of the CPU of the routers if applicable? I mean if a 2811 with CPU going up to 80% would it be wize to be replaced with a 2911?
Regards,
Nick
09-10-2011 02:31 PM
Nick,
Whether you use 2800 series or 2900, 80% utilization is usually high, unless you are connected to the Internet and carry full routing table with limited memory. Do you have large BGP routing table? what does "sh cpu pros" shows?
HTH
09-10-2011 05:34 PM
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Posting
2811 is rated by Cisco at 120 Kpps, the 2911 at 352 Kpps. So it's possible, but not guaranteed, that the newer 2911 will decrease your CPU usage by the same ratio, i.e. from 80% to about 27%.
09-10-2011 05:57 PM
80% cpu is always bad whether it is 2811 or 2911. Before moving to 2911, try checking on 2811 what is the reason which is causing the high cpu and if you can lower it down. May be you are deploying complete routing and that the reason cpu is raising.
Sweta
09-11-2011 04:00 AM
Hi Nick,
could you please post this command out put
show proc cpu | excl 0.00%__0.00%__0.00%
09-11-2011 10:48 PM
LOGBG#sh proc c h
LOGBG 08:45:55 AM Monday Sep 12 2011 EEST
666666666655555888886666666666666666666655555555555555544444
444441111155555111117777777777999999999955555222228888888888
100
90
80 *****
70 *************************
60 ********************************************* *****
50 ************************************************************
40 ************************************************************
30 ************************************************************
20 ************************************************************
10 ************************************************************
0....5....1....1....2....2....3....3....4....4....5....5....6
0 5 0 5 0 5 0 5 0 5 0
CPU% per second (last 60 seconds)
575666657557855444433532325534232232233356223211321111111111
879570011944552304574293568858454219753553610416482062764519
100
90 *
80 * *
70 * ** * **
60 ******* ** *** ** **
50 ######***#####* * * ** * **
40 #######*######****** ** * **** * * ***
30 #################****** **##** * ***##*#** * **
20 ##############################*###########*##* *** * ** * *
10 ############################################################
0....5....1....1....2....2....3....3....4....4....5....5....6
0 5 0 5 0 5 0 5 0 5 0
CPU% per minute (last 60 minutes)
* = maximum CPU% # = average CPU%
672274435367443763347882222443224343445844447342313665343334888998898997
325622124252824962854758444096785298131064186890564918839241544552769367
100 ** * *
90 ** * ** *****
80 * ** * * ************
70 * * ** ** *** * * * *******#****
60 ** * ** ** *** * * *** ****#**#**#*
50 ** * * *** ** **** * * * *** ** * *** ***##**####*
40 ** *** * **** ** ***** *** * ************* * ****** ***#########*
30 *********************#** ******************** * **********#*##########
20 ******#***#****#****###****************##*#**********###**##############
10 ########################################################################
0....5....1....1....2....2....3....3....4....4....5....5....6....6....7..
0 5 0 5 0 5 0 5 0 5 0 5 0
CPU% per hour (last 72 hours)
* = maximum CPU% # = average CPU%
LOGBG#
LOGBG#show proc cpu | excl 0.00%__0.00%__0.00%
CPU utilization for five seconds: 62%/56%; one minute: 58%; five minutes: 50%
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
2 272828 293557 929 0.07% 0.11% 0.08% 0 Load Meter
3 1008 237 4253 0.00% 0.48% 0.12% 514 SSH Process
4 3645068 222629 16372 0.00% 0.17% 0.16% 0 Check heaps
32 38284 1467725 26 0.07% 0.00% 0.00% 0 GraphIt
37 106084 615653 172 0.07% 0.01% 0.00% 0 Net Background
41 3294548 1467831 2244 0.31% 0.30% 0.28% 0 Per-Second Jobs
51 668700 24732 27037 0.00% 0.03% 0.00% 0 Per-minute Jobs
55 30864 440026 70 0.07% 0.00% 0.00% 0 HC Counter Timer
64 164144 5867890 27 0.07% 0.02% 0.00% 0 Netclock Backgro
105 65222224 51633232 1263 3.19% 3.96% 3.48% 0 IP Input
114 123500 1466986 84 0.07% 0.01% 0.00% 0 Spanning Tree
129 146028 2273125 64 0.00% 0.02% 0.00% 0 CEF: IPv4 proces
149 66800 2862115 23 0.07% 0.01% 0.00% 0 Inspect process
152 64936 2862101 22 0.07% 0.00% 0.00% 0 CCE DP URLF cach
160 7925468 352843182 22 1.91% 2.13% 2.10% 0 HQF Shaper Backg
180 19776 9640 2051 0.00% 0.03% 0.00% 0 TPLUS
206 190112 7333659 25 0.00% 0.03% 0.01% 0 Atheros LED Ctro
244 1691236 2888208 585 0.15% 0.18% 0.17% 0 IP NAT Ager
246 149624 2186849 68 0.07% 0.01% 0.00% 0 IP VFR proc
248 996848 1137371 876 0.00% 0.04% 0.04% 0 IP SNMP
249 254144 565129 449 0.00% 0.01% 0.00% 0 PDU DISPATCHER
250 870884 565199 1540 0.00% 0.03% 0.02% 0 SNMP ENGINE
254 2219252 7973160 278 0.15% 0.15% 0.14% 0 NAT MIB Helper
LOGBG#
Here it is. Note that we started work 45 minutes ago.
09-11-2011 10:55 PM
What is the IOS version?
What is your WAN speed?
09-11-2011 10:59 PM
LOGBG#sh ver
Cisco IOS Software, 2800 Software (C2800NM-ADVSECURITYK9-M), Version 12.4(24)T3, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Tue 23-Mar-10 06:43 by prod_rel_team
ROM: System Bootstrap, Version 12.4(1r) [hqluong 1r], RELEASE SOFTWARE (fc1)
LOGBG uptime is 2 weeks, 2 days, 23 hours, 55 minutes
System returned to ROM by power-on
System restarted at 09:01:46 EEST Fri Aug 26 2011
System image file is "flash:c2800nm-advsecurityk9-mz.124-24.T3.bin"
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
Cisco 2811 (revision 53.51) with 247808K/14336K bytes of memory.
Processor board ID FCZ101470JQ
7 FastEthernet interfaces
1 Serial(sync/async) interface
1 Virtual Private Network (VPN) Module
DRAM configuration is 64 bits wide with parity enabled.
239K bytes of non-volatile configuration memory.
62720K bytes of ATA CompactFlash (Read/Write)
Configuration register is 0x2102
LOGBG#
Find attached the sh tech-support file.
Note that there are 2 internet lines: One ADSL of 12 Mb/s down and 1Mb/s up (f0/1) and one metro internet line with 4Mb/s down and 20Mb/s up f(0/0).
09-12-2011 02:32 AM
Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
From your additional postings, it appears router may be just loaded pushing traffic. If your WAN interfaces tend to load up, i.e. the 12, 4 and 20 Mbps, that would be enough to account for your high CPU load.
Your process CPU loading is a bit higher than it ideally should be, but not enough that it should be a major issue.
I notice this 2811 also has 7 FastEthernet interfaces. Does it do any LAN-to-LAN routing in addition to WAN routing?
If I recall correctly, Cisco recommends at 2811 for only a couple of T1 lines. From my experience, it will top out at 100% at about 20 Mbps duplex.
09-12-2011 04:42 AM
The switch card is used only for monitor session; no inter VLAN routing is performed. So there is a throughput issue here; Can you verify that a 2911 will be a future-proof solution for our scenario?
09-12-2011 10:31 AM
Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Not knowing what you might want to do in the future, cannot guarantee a 2911 will be "future proof". However, Cisco recommends a 2911 for up to 35 Mbps WAN bandwidth and their recommendations tend to be rather conservative. Assuming you don't expect to have more than that, you're likely "future proof".
PS:
Since one of your links is ADSL, wondering if its PPPoE, and if so, if MTU is less than 1500 whether you've configured to allow for that. If not, might account for your IP Input being a higher than necessary.
09-12-2011 04:54 AM
Hi,
the CPU seems to be overloaded due to interrupts.
See
http://www.cisco.com/en/US/products/hw/routers/ps359/products_tech_note09186a00801c2af0.shtml
for issues to check.
HTH,
Milan
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