Cisco WAN :: 2801 High CPU Load / Low Traffic / High Interrupts
Nov 26, 2012
We installed a solution with 2 Cisco 2801, BGP multihomed failover.
1) The router which is currently getting all the traffic gets to 55% to 60% of CPU usage when handling 40 SIP/RTP streams . This equals 10Mbit up/10Mbit down and it showed around 5800 packets TX and around 5800 packets RX, with a majority of them CEF switched. As those figures are way less than the performance figures published by Cisco, we wonder if we made any mistake in setting up our router, or if we can do something to improve the router setup.
2) Does it have an impact on router performance if we increase/decrease RTP packet size, thus increasing or decreasing the pps relative to the consumed bandwidth?
3) If it is not possible to improve router configuration, we also wonder about possible replacement units for those routers. Would a 2901 do a good job? By how much would it rise the capacity? What other models would you recommend if we plan to rise the number of concurrent calls by a factor of 4 or even 8 times of what we have now (so up to 48000 pps and 80Mbit).
Here is what we tried:
- ip route-cache same-interface does not seem to improve anything
- ip flow ingress on or off makes no difference
- disabling the inbound ACL on fa0/0 seems to reduce load by 10%, although I don't understand why - a very high percentage is CPU interrupts, and ACLs are process switched, or not?
- we tried following the Cisco guide for high CPU due to high interrupts, with no success
Here are some usage statistics:
The graphs that we plot via SNMP show a propotional growth/increase of CPU and bandwidth (and thus pps) At the highest loads, we had a bit more than 55% CPU utilization with more than 50% interrupt CPU.
CPU utilization for five seconds: 36%/30%; one minute: 30%; five minutes: 30%
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
127 13140 954 13773 2.00% 0.29% 0.07% 194 SSH Process
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 :
Today I've received reports of slow internet access/activity and have noticed myself that it seems a bit slow today. On the dashboard of our asa 5510 the "outside interface" traffic usage is running constantly high. It's at the top of the graph. How can I tell what is causing the spike in utilization. It usually runs at about 1500-2000 Kbps, and now it's up over 10,000.
We have one Router Cisco 2801 at the customer site and facing issue of having very High CPU coming to 99%.CPU utilization for five seconds: 99%/28%; one minute: 99%; five minutes: 98%
I have in my router 2801, one link with 20 MB WAN Connection, and it is presenting high cpu utilization with 97% Interrupt Errors when start one download.
I exchanged it to another router the 2811 and it presented the same results. I read the cisco document about Router Performance.
And it speaks about the 2801 supports 46 Mbps using CEF/Fast Switching and 1.5Mbps using only Process Switching, and 2811 supports 61.44 CEF and 1.5Mbps Process Switching.
I need to know if the NAT Process is process switching or CEF Switching. Because if it was process switching the router is working in the max capacity and i will need to exchange the hardware to a better hardware.
I have problems with the Router 2801.When i give the command show processes cpu, the command show me that the router is working in 98%.
I have vlans like voice vlan and others, I have one 20 Mb Wan Link and I redirect all traffic from my lan to this link and when i browse in internet or i do downloads the router goes to 98%, when i don't make it the router processes goes down.
I thought be problem with hardware, but i exchange to another router and the same problem happened.Before this situation, I had one link with 12 Mb and nothing happened, when i exchange this to the 20 mb link the problems starting.
We have cisoc 2821 at one of branch and created five sub inetrfaces for different vlans.Output of Show interface shows very frequent increase in the input error count.I have changed the physical cable and switch port on the other side.But still error rate is increasing.When the traffic is less error rate is low but with high traffic it is increasing drastically.My router process is very less(4%) only.What could be possible reason. [code]
I found cpu load around 90 - 100% on cisco 3845, so I show tech-spec and show log on router and found process "Virtual Exec" use high load. I'm not sure this situation make high latency time on my network.
we have a pair of 7609 routers working in Active Standby mode. The version of routers are :- Cisco IOS Software, c7600rsp72043_rp Software (c7600rsp72043_rp-ADVIPSERVICESK9-M), Version 12.2(33)SRD4, RELEASE SOFTWARE (fc2)
Quiet frequently we are getting High CPU load problems on our router and this load comes down below 10 % automatically.
I am attaching the Show tech support for your kind consideration.
Similar issue was reported yesterday as well for which i have attached SH tech suppot.
I have a Cisco 2611XM (MPC860P) that i use at home, purchased it when i enrolled in my CCNA certification.
It never occured to me that i had an issue with this router. I have 10Mbps uplink at home, and sometimes its really slow, when i talked to my ISP, we did a lot of troubleshooting to see why we had high latency, but as it turns out, the issue is My Router.
I only have a few machines inside my local LAN so i never even thought this could happen. When i download a file using the 10Mb/s connection, the CPU load goes in less than 1 minute to 99%.
I thought it might be the IOS version of it, and upgraded it to a newer version, with the same results. Here is an output of it:
router1#show processes cpu sort CPU utilization for five seconds: 99%/67%; one minute: 45%; five minutes: 13% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
We have two core switches in our network (Cisco WS-4503). HSRP is working as Active-Standby mode. Recently it has been found that core 1 (which is in active mode) shown high CPU load (60% - 100%). Also found that the below mentioned process takes more CPU. Our network consist of around 30 Vlans. We have already checked for the solution in Cisco website [URL] but couldn't find exact reason. see the below outputs for core 1 switch.
Core1# sh processes cpu sorted CPU utilization for five seconds: 55%/3%; one minute: 65%; five minutes: 71%PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 30 1606933521086983644 147 24.79% 29.93% 35.85% 0 Cat4k Mgmt LoPri 29
I have a 7206VXR router doing policy routing with CEF enabled on all interfaces, no Cache Misses, Align Errors or failed buffers. CPU peaks up to 80% every two or three minutes. I suspect it is traffic related as I have a standby box and when it becomes the active on in the HSRP pair to high CPU load and LAN interface input errors follows it. see various show command output below. The router has a NPE-G1 and I'm using a gigabit port off of this on the LAn side and a E3 Frame Relay interface on the WAN side.
UK-DHC-Policy1#show buffersBuffer elements: 1118 in free list (1000 max allowed) 3539658545 hits, 0 misses, 1119 created Public buffer pools:Small buffers, 104 bytes (total 50, permanent 50, peak 229 @
My understanding is for insight to outside we need global and NAT, and for outside to inside we need static and ACL? Traffic goes to high to low, I'm just start working with 5505 recently.
I purchased the AE3000 Wireless Adapter for my PC, and has been working fine until now. When I first start my PC, my ping starts anywhere between 20-80, then after I try to access anything on the internet it shoots up between 600-1200. It just started happening about 3 days ago, but now it has gotten worse. I can't play any online games, and websites are slow to load.
We are having issues with our Cisco 2811 when there a lot of traffic on the device. Usually the router is down around 5%-10%. Total traffic might be around 2.0 MB. This is a router we are using at a remote campus. We do HD video conferencing every friday. We have a 10 MB internet connection that has our VPN connection to the main campus on it. While doing these VTC, the totall traffic is about 6 MB. The CPU Utilization then rises to approx 75% cause call issues and loss of sound. With another test with no one using the connection for anything else the utilization went up to 35%. The router has 128 MB Ram in it. Does the router need more RAM or do we need a larger internet pipe.
I have little experience with firewalls, what I've learned has been by dealing with issues like this that arise from time to time.I know, I need to upgrade the version. It's in the works now. Anyways, my question/problem is: Today I've received reports of slow internet access/activity and have noticed myself that it seems a bit slow today. On the dashboard of our asa 5510 the "outside interface" traffic usage is running contstantly high. It's at the top of the graph. How can I tell what is causing the spike in utilization. It usually runs at about 1500-2000 Kbps, and now it's up over 10,000.
i recently identified all switch ports in my network on 6509 core were Transmitting Mail server Exchange traffic that was destined for Unicast NLB cluster. and it was impacting various HOST machines NIC cards/performance.After reading this article, i moved NLB CAS servers behind a dedicated cisco Switch.
[URL]
Now My core switch can learn mac address across its trunk port where CAS servers are connected on dedicated switch. but still i can see traffic Transmitting out to my all switch ports of same VLAN ( same as NLB VLAN).
i have a 3560 connecting to a sp with limited bandwidth. i have one interface on the switch whose traffic i do not want to drop. i want this traffic to go into the high priority queue. i am not sure how this should be configured, but here is my best guess and my current qos configuration on the switch:
CPU utilization for five seconds: 61%/59%; one minute: 62%; five minutes: 63% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 578 5856 9392486 0 0.55% 0.50% 0.50% 0 IP SLAs XOS Even 231 90364 576908
When a physical switchport/routed port has high usage, you can move the link to a higher capacity port, upgrade the port, bond links, etc. What exactly do you do when an SVI has high usage? I guess you could remove some servers from the VLAN, but that doesn't seem like a reasonable solution. What dictates the capacity of an SVI? The backplane of the switch?
I always test ethernet family links(E, Fa, Gi) sending pings with MTU equal to 1500. Since most hosts uses MTU 1500 I think is not necessary to test using a high MTU size like 18024.
Our Router 7606 is in a problem with high CPU Utilization. We are using one EBGP and one IBGP session. We are also running OSPF with area 0 between two IBGP router to exchange few local networks. When bandwidth cross 100 MB than only CPU use become 100%. when bandwidth consumption is 80MB CPU use become 80% end so on.
Out put is when bandwidth consumption is 34MB
CPU utilization for five seconds: 44%/43%; one minute: 42%; five minutes: 30% PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process 78 44 9625 4 0.39% 0.03% 0.00% 2 Virtual Exec 13 40 375 106 0.07% 0.00% 0.00% 0 ARP Input 30 116 1098 105 0.07% 0.01% 0.00% 0 IPC Seat Manager
I have a hight CPU utilisation problem in my CISCO7609-S routers. the cpu utilisation can rise 99% et this is usually. In the moment of hight CPU the the process CPU give the following:
I have a 1841 router plugged into a 100M Comcast ethernet connection. My router cpu is really high and users download speed isn't as high as before. Can a 1841 handle 100M circuit with 100 users on it? What would cause the router's cpu to be high? I don't think there are any viruses or malware on the lan.
#sh proc cpu his r2.leaguecity-toy-startoy 06:06:26 PM Wednesday May 30 2012 PST 111 1 1 1 111 24 1 1 1 1 400369232222544222330359645223283294332688334452308404382236
I've noticed a strange behaviour in my 2960s regarded to CPU.
CPU level is very high, 70-75% when nobody is logged by vty or console, but it drops drastically to 40% when sombebody logs in. I've been able to discover that this is due to CPU interrupt level, as it shows the output of sh process cpu sort 5sec, just logged in.
RH0A01-SW1-10G#sh proces cpu sorted 5sec CPU utilization for five seconds: 68%/37%; one minute: 67%; five minutes: 50%
...Some seconds after logged in...
RH0A01-SW1-10G#sh proces cpu sorted 5sec CPU utilization for five seconds: 35%/11%; one minute: 52%; five minutes: 48%
