Debug/syslog configuration commands

Event notification logging

Automatically sends switch-level event messages to the switch's Event Log. Debug and syslog do not affect this operation, but add the capability of directing Event Log messaging to an external device.

logging command


Enables syslog messaging to be sent to the specified IP address. IPv4 and IPv6 are supported.


(Optional) The logging facility command specifies the destination (facility) subsystem used on a syslog server for debug reports.


A text string associated with the values of facility, severity, and system-module.


Sends Event Log messages of equal or greater severity than the specified value to configured debug destinations. (The default setting is to send Event Log messages from all severity levels.)


Sends Event Log messages from the specified system module to configured debug destinations. The severity filter is also applied to the system-module messages you select.

The default setting is to send Event Log messages from all system modules. To restore the default setting, enter the no logging system-module <system-module> or logging system-module all-pass commands.


Sends debug logging to configured debug destinations for all ACL, Event Log, IP-OSPF, and IP-RIP options.


logging: Disables or re-enables syslog logging on one or more syslog servers configured with the logging syslog-ip-addr command.session: Assigns or re-assigns destination status to the terminal device that was most recently used to request debug output.buffer: Enables syslog logging to send the debug message types specified by the debug <debug-type> command to a buffer in switch memory.


Sends standard Event Log messages to configured debug destinations. (The same messages are also sent to the switch's Event Log, regardless of whether you enable this option.)


forwarding: Sends IPv4 forwarding messages to the debug destinations.packet: Sends IPv4 packet messages to the debug Sends RIP event logging to the debug destinations.


dhcpv6-client: Sends DHCPv6 client debug messages to the configured debug destination.forwarding: Sends IPv6 forwarding messages to the debug destination(s)nd: Sends IPv6 debug messages for IPv6 neighbor discovery to the configured debug destinations.packet: Sends IPv6 packet messages to the debug destinations.


Sends LLDP debug messages to the debug destinations.


Sends SSH debug messages at the specified level to the debug destination. The levels are fatal, error, info, verbose, debug, debug2, and debug3.

Using the Debug/Syslog feature, you can perform the following operations:
  • Configure the switch to send Event Log messages to one or more Syslog servers. In addition, you can configure the messages to be sent to the User log facility (default) or to another log facility on configured Syslog servers.

  • Configure the switch to send Event Log messages to the current management- access session (serial-connect CLI, Telnet CLI, or SSH).

  • Disable all Syslog debug logging while retaining the Syslog addresses from the switch configuration. This allows you to configure Syslog messaging and then disable and re-enable it as needed.

  • Display the current debug configuration. If Syslog logging is currently active, the list f configured Syslog servers is displayed.

  • Display the current Syslog server list when Syslog logging is disabled.