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Syslog Questions

July 14th, 2019 in ROUTE 300-101 Go to comments

Question 1

Explanation

The Message Logging is divided into 8 levels as listed below:

Level Keyword Description
0 emergencies System is unusable
1 alerts Immediate action is needed
2 critical Critical conditions exist
3 errors Error conditions exist
4 warnings Warning conditions exist
5 notification Normal, but significant, conditions exist
6 informational Informational messages
7 debugging Debugging messages

The highest level is level 0 (emergencies). The lowest level is level 7. If you specify a level with the “logging console level” command, that level and all the higher levels will be displayed. For example, by using the “logging console warnings” command, all the logging of emergencies, alerts, critical, errors, warnings will be displayed.

Question 2

Explanation

Syslog can be configured to send messages to an external server for storing. The storage size does not depend on the router’s resources and is limited only by the available disk space on the external Syslog server. For example, to instruct our router to send Syslog messages to 192.168.1.2 we can simply use only this command (all parameters are at default values):

R1(config)#logging 192.168.1.2

We cannot send other options (terminal, buffer, console) to external server.

Question 3

Explanation

The “service timestamps log uptime” enables timestamps on log messages, showing the time since the system was rebooted. For example:

00:00:46: %LINK-3-UPDOWN: Interface Port-channel1, changed state to up

Question 4

Explanation

Syslog levels are listed below:

Level Keyword Description
0 emergencies System is unusable
1 alerts Immediate action is needed
2 critical Critical conditions exist
3 errors Error conditions exist
4 warnings Warning conditions exist
5 notification Normal, but significant, conditions exist
6 informational Informational messages
7 debugging Debugging messages

Number “5” in “%LINEPROTO-5- UPDOWN” is the severity level of this message so in this case it is “notification”.

Question 5

Explanation

Maybe this question wants to mention about this Syslog message:

00:00:47: %LINK-3-UPDOWN: Interface GigabitEthernet1/0/1, changed state to up

-> The log secerity level of this warning is 3 – errors

Question 6

Question 7

Question 8

Explanation

“Increase the logging history” here is same as “increase the logging buffer”. The default buffer size is 4096 bytes. By increasing the logging buffer size we can see more history logging messages. But do not make the buffer size too large because the access point could run out of memory for other tasks. We can write the logging messages to a outside logging server instead.

Comments
  1. Marcus
    March 22nd, 2018

    Q8 is not clear enough. The ‘msec’ option doesn’t ENABLE service timestamp. It just EXPANDS service timestamp thereby it will include milliseconds in timestamp.

  2. fffhgf
    August 11th, 2018

    si,plsrty

  3. DRCISCO
    October 6th, 2019

    Hello Guys, Why I can’t see the questions anywhere on this website? is there a trick?! It’s not clickable

  4. Anonymous
    January 21st, 2020

    @DRCISCO – you have to pay

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