Cisco Nexus 7000 Series NX-OS System Management Configuration Guide, Release 6.x
Configuring System Message Logging
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Table of Contents

Configuring System Message Logging

Finding Feature Information

Information About System Message Logging

syslog Servers

Virtualization Support

Licensing Requirements for System Message Logging

Guidelines and Limitations

Default Settings

Configuring System Message Logging

Configuring System Message Logging to Terminal Sessions

Logging System Messages to a File

Configuring Module and Facility Messages Logged

Configuring syslog Servers

Displaying and Clearing Log Files

Verifying the System Message Logging Configuration

Configuration Example for System Message Logging

Additional References

Related Documents

Standards

Feature History for System Message Logging

Finding Feature Information

Your software release might not support all the features documented in this module. For the latest caveats and feature information, see the Bug Search Tool at https://tools.cisco.com/bugsearch and the release notes for your software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the “New and Changed Information” chapter or the Feature History table below.

Information About System Message Logging

You can use system message logging to control the destination and to filter the severity level of messages that system processes generate. You can configure logging to terminal sessions, a log file, and syslog servers on remote systems.

System message logging is based on RFC 3164 . For more information about the system message format and the messages that the device generates, see the Cisco NX-OS System Messages Reference .

By default, the device outputs messages to terminal sessions. For information about configuring logging to terminal sessions, see the “Configuring System Message Logging to Terminal Sessions” section.

By default, the device logs system messages to a log file. For information about configuring logging to a file, see the “Logging System Messages to a File” section.

Table 6-1 describes the severity levels used in system messages. When you configure the severity level, the system outputs messages at that level and lower.

.

Table 6-1 System Message Severity Levels

Level
Description

0 – emergency

System unusable

1 – alert

Immediate action needed

2 – critical

Critical condition

3 – error

Error condition

4 – warning

Warning condition

5 – notification

Normal but significant condition

6 – informational

Informational message only

7 – debugging

Appears during debugging only

The device logs the most recent 100 messages of severity 0, 1, or 2 to the NVRAM log. You cannot configure logging to the NVRAM.

You can configure which system messages should be logged based on the facility that generated the message and its severity level. For information about facilities, see the Cisco Nexus 7000 Series NX-OS System Management Command Reference . For information about configuring the severity level by module and facility, see the “Configuring Module and Facility Messages Logged” section.

This section includes the following topics:

syslog Servers

The syslog servers run on remote systems that log system messages based on the syslog protocol. You can configure up to eight IPv4 or IPv6 syslog servers. For information about configuring syslog servers, see the “Configuring syslog Servers” section.


Note When the device first initializes, messages are sent to syslog servers only after the network is initialized.


Virtualization Support

A virtual device context (VDC) is a logical representation of a set of system resources. System message logging applies only to the VDC where commands are entered.

For information about configuring VDCs, see the Cisco Nexus 7000 Series NX-OS Virtual Device Context Configuration Guide .

Licensing Requirements for System Message Logging

 

Product
License Requirement

Cisco NX-OS

System message logging requires no license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide .

Guidelines and Limitations

System messages are logged to the console and the logfile by default.

Default Settings

Table 6-2 lists the default settings for system message logging parameters.

 

Table 6-2 Default System Message Logging Parameters

Parameters
Default

Console logging

Enabled at severity level 2

Monitor logging

Enabled at severity level 5

Log file logging

Enabled to log messages at severity level 5

Module logging

Enabled at severity level 5

Facility logging

Enabled; for severity levels, see the Cisco Nexus 7000 Series NX-OS System Management Command Reference

Time-stamp units

Seconds

syslog server logging

Disabled

Configuring System Message Logging

This section includes the following topics:


Note Be aware that the Cisco NX-OS commands for this feature may differ from those commands used in Cisco IOS.


Configuring System Message Logging to Terminal Sessions

You can configure the device to log messages by their severity level to console, Telnet, and SSH sessions.

By default, logging is enabled for terminal sessions.


Tip The current critical (default) logging level is maintained if the console baud speed is 9600 baud (default). All attempts to change the console logging level generate an error message. To increase the logging level (above critical), you must change the console baud speed to 38400 baud.


BEFORE YOU BEGIN

Make sure that you are in the correct VDC. To change the VDC, use the switchto vdc command.

SUMMARY STEPS

1. terminal monitor

2. config t

3. logging console [ severity-level ]

no logging console

4. show logging console

5. logging monitor [ severity-level ]

no logging monitor

6. show logging monitor

7. logging message interface type ethernet description

no logging message interface type ethernet description

8. copy running-config startup-config

 

Command
Purpose

Step 1

terminal monitor

 

Example:

switch# terminal monitor

Enables the device to log messages to the console.

Step 2

config t

 

Example:

switch# config t

Enter configuration commands, one per line. End with CNTL/Z.

switch(config)#

Places you in global configuration mode.

Step 3

logging console [ severity-level ]

 

Example:

switch(config)# logging console 3

Configures the device to log messages to the console session based on a specified severity level or higher. Severity levels, which can range from 0 to 7, are listed in Table 6-1 . If the severity level is not specified, the default of 2 is used.

no logging console [ severity-level ]

 

Example:

switch(config)# no logging console

Disables the device’s ability to log messages to the console.

Step 4

show logging console

 

Example:

switch(config)# show logging console

(Optional) Displays the console logging configuration.

Step 5

logging monitor [ severity-level ]

 

Example:

switch(config)# logging monitor 3

Enables the device to log messages to the monitor based on a specified severity level or higher. The configuration applies to Telnet and SSH sessions. Severity levels, which can range from 0 to 7, are listed in Table 6-1 . If the severity level is not specified, the default of 2 is used.

no logging monitor [ severity-level ]

 

Example:

switch(config)# no logging monitor

Disables logging messages to Telnet and SSH sessions.

Step 6

show logging monitor

 

Example:

switch(config)# show logging monitor

(Optional) Displays the monitor logging configuration.

Step 7

logging message interface type ethernet description

 

Example:

switch(config)# logging message interface type ethernet description

Enables you to add the description for physical Ethernet interfaces and subinterfaces in the system message log. The description is the same description that was configured on the interface.

no logging message interface type ethernet description

 

Example:

switch(config)# no logging message interface type ethernet description

Disables the printing of the interface description in the system message log for physical Ethernet interfaces.

Step 8

copy running-config startup-config

 

Example:

switch(config)# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

Logging System Messages to a File

You can configure the device to log system messages to a file. By default, system messages are logged to the file log:messages.

For information about displaying and clearing log files, see the “Displaying and Clearing Log Files” section.

BEFORE YOU BEGIN

Make sure that you are in the correct VDC. To change the VDC, use the switchto vdc command.

SUMMARY STEPS

1. config t

2. logging logfile logfile-name severity-level [ size bytes ]

no logging logfile [ logfile-name severity-level [ size bytes ]]

3. logging event {link-status | trunk-status} {enable | default}

4. show logging info

5. copy running-config startup-config

 

Command
Purpose

Step 1

config t

 

Example:

switch# config t

Enter configuration commands, one per line. End with CNTL/Z.

switch(config)#

Places you in global configuration mode.

Step 2

logging logfile logfile-name severity-level [ size bytes ]

 

Example:

switch(config)# logging logfile my_log 6

Configures the name of the log file used to store system messages and the minimum severity level to log. You can optionally specify a maximum file size. The default severity level is 5 and the file size is 10485760. Severity levels are listed in Table 6-1 . The file size is from 4096 to 4194304 bytes.

no logging logfile [ logfile-name severity-level [ size bytes ]]

 

Example:

switch(config)# no logging logfile

Disables logging to the log file.

Step 3

logging event {link-status | trunk-status} {enable | default}

 

Example:

switch(config)# logging event link-status default

Logs interface events.

  • link-status —Logs all UP/DOWN and CHANGE messages.
  • trunk-status —Logs all TRUNK status messages.
  • enable —Specifies to enable logging to override the port level configuration.
  • default —Specifies that the default logging configuration is used by interfaces not explicitly configured.

Step 4

show logging info

 

Example:

switch(config)# show logging info

(Optional) Displays the logging configuration.

Step 5

copy running-config startup-config

 

Example:

switch(config)# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

Configuring Module and Facility Messages Logged

You can configure the severity level and time-stamp units of messages logged by modules and facilities.

BEFORE YOU BEGIN

Make sure that you are in the correct VDC. To change the VDC, use the switchto vdc command.

SUMMARY STEPS

1. config t

2. logging module [ severity-level ]

no logging module

3. show logging module

4. logging level facility severity-level

no logging level [ facility severity-level ]

5. show logging level [ facility ]

6. logging timestamp { microseconds | milliseconds | seconds }

no logging timestamp { microseconds | milliseconds | seconds }

7. show logging timestamp

8. copy running-config startup-config

 

Command
Purpose

Step 1

config t

 

Example:

switch# config t

Enter configuration commands, one per line. End with CNTL/Z.

switch(config)#

Places you in global configuration mode.

Step 2

logging module [ severity-level ]

 

Example:

switch(config)# logging module 3

Enables module log messages that have the specified severity level or higher. Severity levels, which range from 0 to 7, are listed in Table 6-1 . If the severity level is not specified, the default of 5 is used.

no logging module [ severity-level ]

 

Example:

switch(config)# no logging module

Disables module log messages.

Step 3

show logging module

 

Example:

switch(config)# show logging module

(Optional) Displays the module logging configuration.

Step 4

logging level facility severity-level

 

Example:

switch(config)# logging level aaa 2

Enables logging messages from the specified facility that have the specified severity level or higher. The facilities are listed in the Cisco Nexus 7000 Series NX-OS System Management Command Reference . Severity levels, which range from 0 to 7, are listed in Table 6-1 . To apply the same severity level to all facilities, use the all facility. For defaults, see the show logging level command.

no logging level [ facility severity-level ]

 

Example:

switch(config)# no logging level aaa 3

Resets the logging severity level for the specified facility to its default level. If you do not specify a facility and severity level, the device resets all facilities to their default levels.

Step 5

show logging level [ facility ]

 

Example:

switch(config)# show logging level aaa

(Optional) Displays the logging level configuration and the system default level by facility. If you do not specify a facility, the device displays levels for all facilities.

Step 6

logging timestamp { microseconds | milliseconds | seconds }

 

Example:

switch(config)# logging timestamp milliseconds

Sets the logging time-stamp units. By default, the units are seconds.

Note This command applies to logs that are kept in the switch. It does not apply to the external logging server.

no logging timestamp { microseconds | milliseconds | seconds }

 

Example:

switch(config)# no logging timestamp milliseconds

Resets the logging time-stamp units to the default of seconds.

Note This command applies to logs that are kept in the switch. It does not apply to the external logging server.

Step 7

show logging timestamp

 

Example:

switch(config)# show logging timestamp

(Optional) Displays the logging time-stamp units configured.

Step 8

copy running-config startup-config

 

Example:

switch(config)# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

Configuring syslog Servers

You can configure up to eight syslog servers that reference remote systems where you want to log system messages.


Note We recommend that you configure the syslog server to use the management virtual routing and forwarding (VRF) instance. For more information on VRFs, see the Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide.


BEFORE YOU BEGIN

Make sure that you are in the correct VDC. To change the VDC, use the switchto vdc command.

SUMMARY STEPS

1. config t

2. logging server host [ severity-level [ use-vrf vrf-name ]]

no logging server host

3. logging source-interface loopback virtual-interface

4. show logging server

5. copy running-config startup-config

 

Command
Purpose

Step 1

config t

 

Example:

switch# config t

Enter configuration commands, one per line. End with CNTL/Z.

switch(config)#

Places you in global configuration mode.

Step 2

logging server host [ severity-level [ use-vrf vrf-name ]]

 

Example 1:

switch(config)# logging server 192.0.2.253

 

Example 2:

switch(config)# logging server 2001::)db*::3 5 use-vrf red

Configures a syslog server at the specified hostname or IPv4 or IPv6 address. You can limit logging of messages to a particular VRF by using the use-vrf keyword. In Cisco NX-OS Release 4.2 or higher, the default VRF is default. Severity levels, which range from 0 to 7, are listed in Table 6-1 . The default outgoing facility is local7.

Example 1 forwards all messages on facility local 7.

Example 2 forwards messages with severity level 5 or lower for VRF red.

no logging server host

 

Example:

switch(config)# no logging server host

Removes the logging server for the specified host.

Step 3

logging source-interface loopback virtual-interface

 

Example:

switch(config)# logging source-interface loopback 5

Enables a source interface for the remote syslog server. The range for the virtual-interface argument is from 0 to 1023.

Step 4

show logging server

 

Example:

switch(config)# show logging server

(Optional) Displays the syslog server configuration.

Step 5

copy running-config startup-config

 

Example:

switch(config)# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

You can configure a syslog server on a UNIX or Linux system by adding the following line to the /etc/syslog.conf file:

facility.level <five tab characters> action
 

Table 6-3 describes the syslog fields that you can configure.

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Table 6-3 syslog Fields in syslog.conf

Field
Description

Facility

Creator of the message, which can be auth, authpriv, cron, daemon, kern, lpr, mail, mark, news, syslog, user, local0 through local7, or an asterisk (*) for all. These facility designators allow you to control the destination of messages based on their origin.

Note Check your configuration before using a local facility.

Level

Minimum severity level at which messages are logged, which can be debug, info, notice, warning, err, crit, alert, emerg, or an asterisk (*) for all. You can use none to disable a facility.

Action

Destination for messages, which can be a filename, a hostname preceded by the at sign (@), a comma-separated list of users, or an asterisk (*) for all logged-in users.

To configure a syslog server on a UNIX or Linux system, follow these steps:


Step 1 Log debug messages with the local7 facility in the file /var/log/myfile.log by adding the following line to the /etc/syslog.conf file:

debug.local7 /var/log/myfile.log
 

Step 2 Create the log file by entering these commands at the shell prompt:

$ touch /var/log/myfile.log
$ chmod 666 /var/log/myfile.log
 

Step 3 Make sure the system message logging daemon reads the new changes by checking myfile.log after entering this command:

$ kill -HUP ~cat /etc/syslog.pid~
 


 

Displaying and Clearing Log Files

You can display or clear messages in the log file and the NVRAM.

BEFORE YOU BEGIN

Make sure that you are in the correct VDC. To change the VDC, use the switchto vdc command.

SUMMARY STEPS

1. show logging last number-lines

2. show logging logfile [ start-time yyyy mmm dd hh:mm:ss ] [ end-time yyyy mmm dd hh:mm:ss ]

3. show logging nvram [ last number-lines ]

4. clear logging logfile

5. clear logging nvram

 

Command
Purpose

Step 1

show logging last number-lines

 

Example:

switch# show logging last 40

Displays the last number of lines in the logging file. You can specify from 1 to 9999 for the last number of lines.

Step 2

show logging logfile [ start-time yyyy mmm dd hh:mm:ss ] [ end-time yyyy mmm dd hh:mm:ss ]

 

Example:

switch# show logging logfile start-time 2007 nov 1 15:10:0

Displays the messages in the log file that have a time stamp within the span entered. If you do not enter an end time, the current time is used. You enter three characters for the month time field, and digits for the year and day time fields.

Step 3

show logging nvram [ last number-lines ]

 

Example:

switch# show logging nvram last 10

Displays the messages in the NVRAM. To limit the number of lines displayed, you can enter the last number of lines to display. You can specify from 1 to 100 for the last number of lines.

Step 4

clear logging logfile

 

Example:

switch# clear logging logfile

Clears the contents of the log file.

Step 5

clear logging nvram

 

Example:

switch# clear logging nvram

Clears the logged messages in NVRAM.

Verifying the System Message Logging Configuration

To display system message logging configuration information, perform one of the following tasks:

 

Command
Purpose

show logging console

Displays the console logging configuration.

show logging info

Displays the logging configuration.

show logging last number-lines

Displays the last number of lines of the log file.

show logging level [ facility ]

Displays the facility logging severity level configuration.

show logging logfile [ start-time yyyy mmm dd hh:mm:ss ] [ end-time yyyy mmm dd hh:mm:ss ]

Displays the messages in the log file.

show logging module

Displays the module logging configuration.

show logging monitor

Displays the monitor logging configuration.

show logging nvram [ last number-lines ]

Displays the messages in the NVRAM log.

show logging server

Displays the syslog server configuration.

show logging timestamp

Displays the logging time-stamp units configuration.

Example:
switch(config)# show logging timestamp
Logging timestamp: Seconds

For detailed information about the fields in the output from these commands, see the Cisco Nexus 7000 Series NX-OS System Management Command Reference .

Configuration Example for System Message Logging

This example shows how to configure system message logging:

config t
logging console 3
logging monitor 3
logging logfile my_log 6
logging module 3
logging level aaa 2
logging timestamp milliseconds
logging server 172.28.254.253
logging server 172.28.254.254 5 facility local3
copy running-config startup-config
 

Additional References

For additional information related to implementing system message logging, see the following sections:

Related Documents

Related Topic
Document Title

System messages CLI commands

Cisco Nexus 7000 Series NX-OS System Management Command Reference

System messages

Cisco NX-OS System Messages Reference

Standards

Standards
Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.

Feature History for System Message Logging

Table 6-4 lists the release history for this feature.

 

Table 6-4 Feature History for System Message Logging

Feature Name
Releases
Feature Information

System message logging

5.2(1)

Added the ability to add the description for physical Ethernet interfaces and subinterfaces in the system message log.

Syslog servers

5.1(1)

Increased the number of supported syslog servers from three to eight.

IPv6 support

4.2(1)

Added support for IPv6 syslog hosts.

System message logging

4.0(1)

This feature was introduced.