How to view Log on the cisco 2821 Router

Question

Hi,
can any one help me  to view the Log on the Cisco 2821 router for any  issue occur.
Thanks,
Saroj

Answer 1

Cisco devices use the syslog to manage system logs and alerts. But in Cisco devices there is lack of large internal storage space for storing these kinds of logs.So to overcome Cisco devices has the following two options:
1) internanal buffer — That is a small part of memory buffers to collect log the most recent messages. The buffer size is limited and , when the device reboots, these syslog messages are lost.by default it is on
(If not follow this steps
conf t
logging on
logging console.....console logs
logging buffer  size ......set the size of buffer
terminal monitor.......to gets logs on the remote terminal like telnet,ssh etc.
sh logging.........to see buffer logs.)
2) Syslog server—  By using this we can send messages to an external device for storing this logs and the storage size does depend on the available disk space of the external syslog server. This option is not enabled by default.
If you have any syslog server please find the below simple config .
conf t
logging host x.x.x.x
logging traps (i.e 0 1 2 3 4 5 .. according to your requirement)
before enabling logging be sure that your router is properly configure to collect proper time from any NTP server or manually configure to get time
command to set time manually on router is (set clock ) or to use ntp server use ntp server x.x.x.x to sync clock to router router.
Hop thant is informative ,
Regards,
Ashish