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Logging console

As explained in Acing the CCNA Exam: Volume 2 Advanced Networking and Security

logging console is a Cisco IOS command that enables console logging and optionally sets its minimum event severity threshold.

The Cisco IOS logging console command enables real-time Syslog messages on the console line. It is enabled by default and can include a severity threshold. section 7.3 section 7.1.1

Configure and interpret console logging with these rules:

  • Use logging console [severity] in global configuration mode; specifying 4 or warnings logs levels 0 through 4. section 7.2.2
  • Use no logging console to stop displaying Syslog messages on the console line. section 7.1.1
  • Severity levels are inclusive: lower numerical values represent more severe events, while level 7 includes debugging messages. section 7.2.2

Console and VTY comparison

Console users receive real-time messages by default. VTY users additionally need terminal monitor for each Telnet or SSH session; reconnecting or using another session requires the command again. section 7.1.1

SW1(config)# interface g0/1
SW1(config-if)# shutdown                                                            #1
SW1(config-if)# do terminal monitor                                                 #2
SW1(config-if)# no shutdown                                                         #3
Sep 18 02:17:46.867: %LINK-3-UPDOWN: Interface FastEthernet0/3, changed state to up #4 
Sep 18 02:17:47.874: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/3, changed state to up                                                                 #4
#1 No Syslog messages are shown after disabling G0/1.
#2 Enables real-time logging for the session
#3 Reenables the interface
#4 Syslog messages are displayed.

Follow the interface shutdown and reactivation sequence to see terminal monitor expose real-time Syslog messages. section 7.1.1

How Acing the CCNA Exam: Volume 2 Advanced Networking and Security covers it

How deep it goes
Explains enablement, disabling, severity thresholds, defaults, and session differences without descending into Syslog message internals.
Examples
Uses interface shutdown and reactivation commands to demonstrate when console and VTY users see Syslog messages.
What it assumes
Assumes Cisco IOS configuration mode and distinguishes console connections from Telnet or SSH VTY sessions.
What you can do after
Operate console Syslog visibility and filter displayed events with Cisco IOS configuration commands.
How it connects
Connects console logging with Syslog, severity levels, VTY logging, terminal monitor, and real-time event display.
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Acing the CCNA Exam: Volume 2 Advanced Networking and Security. The section links point to the parts of the book it draws on.