Cisco IOS Software, 1841 Software (C1841-ADVENTERPRISEK9-M), Version 15.1(4)M2, RELEASE SOFTWARE (fc1)
When the client on a Branch Office LAN realizes calls to skype, there is a sharp loading of CPU on Branch router Cisco1841 (all Inet traffic goes through DMVPN-Tunnel Interface to proxy on Central Office).
CPU utilization for five seconds: 89%/81%; one minute: 44%; five minutes: 41%
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
121 30971272 10952019 2827 6.65% 5.59% 5.75% 0 IP Input
2 125984 229295 549 1.28% 0.12% 0.10% 0 Load Meter
96 1774568 141763543 12 0.64% 0.75% 0.78% 0 Ethernet Msec Ti
117 515872 35077439 14 0.56% 0.17% 0.16% 0 IPAM Manager
336 2617980 276339056 9 0.48% 1.70% 1.79% 0 IP SLAs Responde
203 929984 275753650 3 0.24% 0.79% 0.86% 0 HQF Shaper Backg
330 796120 55876200 14 0.16% 0.26% 0.28% 0 MFIB_mrib_write
314 414120 11711507 35 0.08% 0.12% 0.10% 0 IGMP Input
315 966264 25445473 37 0.08% 0.21% 0.23% 0 PIM Process
240 278164 35693249 7 0.08% 0.09% 0.08% 0 MMON MENG
TLLN-CE1#sh ip flow top-talkers
SrcIf SrcIPaddress DstIf DstIPaddress Pr SrcP DstP Bytes
Tu253 10.101.0.20 Vl1 10.108.1.32 06 1F90 C709 6974K
Tu253 10.101.0.20 Vl1 10.108.1.32 06 1F90 C72E 3289K
Vl1 10.108.1.32 Tu254* 10.101.0.20 06 C709 1F90 1568K
Tu254 10.100.0.14 Vl1 10.108.1.34 06 0D3D 0408 1311K
Tu253 10.101.1.233 Vl1 10.108.1.37 06 0D3D 040A 541K
5 of 5 top talkers shown. 44 flows processed.
FastEthernet 0/0 - WAN Interface (for Tunnel Source):
TLLN-CE1#sh int f0/0
FastEthernet0/0 is up, line protocol is up
Hardware is Gt96k FE, address is 58bc.2771.5f8e (bia 58bc.2771.5f8e)
Description: WAN
Internet address is x.x.x.x/y
MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
reliability 254/255, txload 1/255, rxload 1/255
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 00:00:13, output 00:00:00, output hang never
Last clearing of "show interface" counters 04:12:34
Input queue: 43/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: Class-based queueing
Output queue: 0/1000/0 (size/max total/drops)
30 second input rate 1909000 bits/sec, 244 packets/sec
30 second output rate 356000 bits/sec, 30 packets/sec
1875022 packets input, 808226627 bytes
Received 535 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
6431 input errors, 0 CRC, 0 frame, 0 overrun, 6431 ignored
0 watchdog
0 input packets with dribble condition detected
763186 packets output, 200182523 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
All Skype traffic application auto mark as DSCP EF, and then router applies the next outbound policy on WAN Fast0/0:
class-map match-any CLASS-VOICE
match ip dscp ef
!
...
!
policy-map POLICY-QOS-OUT
description *** Global QoS Policy ***
class CLASS-ROUTING
bandwidth percent 3
class CLASS-VOICE
priority percent 18
class CLASS-VIDEO-CONF
priority percent 15
class CLASS-STREAM-VIDEO
bandwidth percent 10
class CLASS-MISSION-CRIT
bandwidth percent 12
random-detect dscp-based
random-detect dscp 25 32 40
class CLASS-VOICE-CONTROL
bandwidth percent 2
class CLASS-TRANSACT
bandwidth percent 8
random-detect dscp-based
random-detect dscp 25 32 40
class CLASS-NETWORK-MGMT
bandwidth percent 2
class CLASS-BULK
bandwidth percent 8
random-detect dscp-based
random-detect ecn
random-detect dscp 25 32 40
class CLASS-SCAVENGER
bandwidth percent 10
class class-default
fair-queue
random-detect dscp-based
random-detect dscp 25 32 40
!
policy-map POLICY-INET-10M-OUT
class class-default
shape average 8500000 850000
service-policy POLICY-QOS-OUT
!
interface FastEthernet0/0
description WAN
ip address x.x.x.x y.y.y.y
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat outside
ip virtual-reassembly in
ip verify unicast reverse-path allow-self-ping 150
load-interval 30
duplex auto
speed auto
service-policy output POLICY-INET-10M-OUT
!
TLLN-CE1#sh ip traffic
IP statistics:
Rcvd: 102808 total, 3682 local destination
0 format errors, 0 checksum errors, 252 bad hop count
0 unknown protocol, 0 not a gateway
0 security failures, 0 bad options, 1337 with options
Opts: 0 end, 0 nop, 0 basic security, 0 loose source route
0 timestamp, 0 extended security, 0 record route
0 stream ID, 0 strict source route, 1337 alert, 0 cipso, 0 ump
0 other
Frags: 0 reassembled, 0 timeouts, 0 couldn't reassemble
90 fragmented, 180 fragments, 0 couldn't fragment
Bcast: 65 received, 1 sent
Mcast: 1476 received, 797 sent
Sent: 100833 generated, 451516 forwarded
Drop: 0 encapsulation failed, 0 unresolved, 0 no adjacency
0 no route, 0 unicast RPF, 0 forced drop
0 options denied
Drop: 0 packets with source IP address zero
Drop: 0 packets with internal loop back IP address
0 physical broadcast
Reinj: 0 in input feature path, 0 in output feature path
ICMP statistics:
Rcvd: 0 format errors, 0 checksum errors, 0 redirects, 190 unreachable
0 echo, 0 echo reply, 0 mask requests, 0 mask replies, 0 quench
0 parameter, 0 timestamp, 0 timestamp replies, 0 info request, 0 other
0 irdp solicitations, 0 irdp advertisements
0 time exceeded, 0 info replies
Sent: 0 redirects, 0 unreachable, 0 echo, 0 echo reply
0 mask requests, 0 mask replies, 0 quench, 0 timestamp, 0 timestamp replies
0 info reply, 0 time exceeded, 0 parameter problem
0 irdp solicitations, 0 irdp advertisements
TCP statistics:
Rcvd: 1018 total, 0 checksum errors, 0 no port
Sent: 1067 total
BGP statistics:
Rcvd: 0 total, 0 opens, 0 notifications, 0 updates
0 keepalives, 0 route-refresh, 0 unrecognized
Sent: 0 total, 0 opens, 0 notifications, 0 updates
0 keepalives, 0 route-refresh
EIGRP-IPv4 statistics:
Rcvd: 0 total
Sent: 0 total
PIMv2 statistics: Sent/Received
Total: 336/685, 0 checksum errors, 0 format errors
Registers: 0/0 (0 non-rp, 0 non-sm-group), Register Stops: 0/0, Hellos: 183/181
Join/Prunes: 105/352, Asserts: 1/105, grafts: 47/0
Bootstraps: 0/0, Candidate_RP_Advertisements: 0/0
Queue drops: 0
State-Refresh: 0/0
IGMP statistics: Sent/Received
Total: 299/713, Format errors: 0/0, Checksum errors: 0/0
Host Queries: 90/30, Host Reports: 209/358, Host Leaves: 0/0
DVMRP: 0/0, PIM: 0/0
Queue drops: 0
UDP statistics:
Rcvd: 907 total, 0 checksum errors, 41 no port
Sent: 974 total, 0 forwarded broadcasts
OSPF statistics:
Last clearing of OSPF traffic counters 00:29:47
Rcvd: 169 total, 0 checksum errors
125 hello, 0 database desc, 0 link state req
31 link state updates, 13 link state acks
Sent: 154 total
125 hello, 0 database desc, 0 link state req
17 link state updates, 12 link state acks
ARP statistics:
Rcvd: 367 requests, 0 replies, 0 reverse, 0 other
Sent: 0 requests, 239 replies (0 proxy), 0 reverse
Drop due to input queue full: 0
What can cause sharp loading of CPU? ...throughput performance 1841, it seems, allows to process traffic
