Trap CPU Utilization

A lot of times, there are problems when you try to connect to the switch by telnet or ssh, the connection is really slow. In some cases, the icmp traffic is dropped. One minute later, the device is back to normal. It is somehow related to the CPU Utilization.  In order to trap the CPU Utilization in syslog. Here is the command to enable it.

Configuration Steps


Make sure that the logging time is accurate.

• service timestamps log datetime localtime

Enable cpu utilization traps.

• process cpu threshold type{interrupt | process | total}rising  <number>  interval <interval>falling <number>

Check CPU Utilization

• show process cpu 

NTP (Network Timing Protocol)

NTP (Network Timing Protocol)

NTP allows time synchronization in to the source clock. NTP uses UDP port 123 to communicate. There are 3 modes of operation.

- Client

- Server

- Symmetric active mode (peer)

We can statically configure server address or let it discover by itself using broadcast command. In this example below, I will show the configuration of statically address configuration.

For broadcast, click here.

Example 

  - Network 192.168.1.1 between R1 and R2

  - Authentication ntp

R1
ntp authentication-key 1 md5 121711075F00091D 7
ntp authenticate
ntp master
!

R2

ntp authentication-key 1 md5 1419061B410F2F32 7

ntp authenticate

ntp trusted-key 1

//Client

ntp server 192.168.1.1 key 1   

//Peer 

ntp peer 192.168.1.1 key 1

Verify configuration 

debug ntp packet

debug ntp authentication

debug ntp event

Mar  1 00:44:37.109:  Authentication key 1

Mar  1 00:44:37.113: NTP: 192.168.1.1 synced to new peer

Mar  1 00:44:37.113: NTP: sync change

Mar  1 00:44:37.113: NTP: peer stratum change

Mar  1 00:44:37.113: NTP: 192.168.1.1 reachable

Check the synchronization between routers

R2#show ntp associations

      address         ref clock     st  when  poll reach  delay  offset    disp

*~192.168.1.1      127.127.7.1       8    30    64   17    59.7  -51.09  1939.3

 * master (synced), # master (unsynced), + selected, - candidate, ~ configured

R2#

R2#sh ntp status

Clock is synchronized, stratum 9, reference is 192.168.1.1

nominal freq is 250.0000 Hz, actual freq is 250.0000 Hz, precision is 2**18

reference time is C0294E35.201800AA (00:47:49.125 UTC Fri Mar 1 2002)

clock offset is -51.0852 msec, root delay is 59.68 msec

root dispersion is 1990.42 msec, peer dispersion is 1939.30 msec

R2#

NTP Broadcast

NTP Broadcast

Configuration Example.

R1
interface FastEthernet0/0
 ip address 192.168.1.1 255.255.255.0
 duplex auto
 speed auto
 ntp broadcast key 1

ntp authentication-key 1 md5 1419061B410F2F32 7

ntp authenticate

R2

interface FastEthernet0/0

 ip address 192.168.1.2 255.255.255.0

 duplex auto

 speed auto

 ntp broadcast client

 ntp broadcast key 1

ntp authentication-key 1 md5 1419061B410F2F32 7

ntp authenticate

ntp trusted-key 1