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Viptela Documentation

Configuring System Logging

On Viptela devices, you can log event notification system log (syslog) messages to files on the local device, or you can log them to files on a remote host.

Log System Log Messages on the Local Device

Logging to the local device's hard disk of syslog messages with a priority level of "information" is enabled by default. The log files are placed in the local /var/log directory. By default, log files are 10 MB in size, and up to 10 files are stored. After 10 files have been created, the oldest one is discarded to create a file for newer syslog messages.

To modify the syslog default parameters on a Viptela device:

Viptela(config)# system logging disk
Viptela(config-logging-disk)# enable
Viptela(config-logging-disk)# file rotate number size megabytes
Viptela(config-logging-disk)# priority priority

By default, 10 syslog files are created. In the rotate command, you can configure this to be a number from 1 through 10.

By default, syslog files are 10 MB. You can configure this to be from 1 to 20 MB.

The priority indicates the severity of syslog messages to save. The default priority value is "informational", so by default, all syslog messages are recorded. The priority level can be one of the following (in order of decreasing severity):

  • emergency—System is unusable (corresponds to syslog severity 0).
  • alert— Action must be taken immediately (corresponds to syslog severity 1).
  • critical—A serious condition (corresponds to syslog severity 2).
  • error—An error condition that does not fully impair system usability (corresponds to syslog severity 3).
  • warn—A minor error condition (corresponds to syslog severity 4).
  • normal—A normal, but significant condition (corresponds to syslog severity 5).
  • information—Routine condition (the default) (corresponds to syslog severity 6).

​To disable the logging of syslog messages to the local disk, use the no system logging disk enable command.

Log System Log Messages to a Remote Device

To log event notification syslog messages to a remote host, configure information about the server:

Viptela(config)# system logging server (dns-name | hostname | ip-address)
Viptela(config-logging-server)# vpn vpn-id
​Viptela(config-logging-server)# priority priority
Viptela(config-logging-server)# source-interface interface-name

Configure the server location by DNS name, hostname, or IP address. You can specify the VPN in which the syslog server is located or through which it can be reached and the outgoing interface to use to reach the server.

You configure the priority of the syslog messages to send to the server as discussed above.

You can configure multiple syslog servers.

​To disable the logging of syslog messages to the local disk, use the no system logging disk enable command.

System Log Files

Syslog messages at or above the default or configured priority value are recorded in a number of files in the directory /var/log:​

  • auth.log—Login, logout, and superuser access events, and usage of authorization systems.​
  • kern.log—Kernel messages.
  • messages—Consolidated log file that contains syslog messages from all sources.
  • vconfd—All configuration-related syslog messages.
  • vdebug—All debug messages for modules whose debugging is turned on and all syslog messages above the configured priority value are saved to the file /var/log/tmplog/ vdebug. Debug logging supports various levels of logging based on the module. Different modules implement the logging levels differently. For example, the system manager (sysmgr) has two logging levels (on and off), while the chassis manager (chmgr) has four different logging levels (off, low, normal, and high). You cannot send debug messages to a remote host. To enable debugging, use the debug operational command.
  • vsyslog—All syslog messages from Viptela processes (daemons) above the configured priority value are stored in the file /var/log/vsyslog. The default priority value is "informational", so by default, all "notice", "warning", "error", "critical", "alert", and "emergency" syslog messages are saved.

The Viptela software does not use the following standard LINUX files, which are present in /var/log, for logging: cron.log, debug, lpr.log, mail.log, and syslog.

Syslog message generated by the Viptela software have the following format:

facility.source date - source - module - level - MessageID: text-of-syslog-message

Here is an example of a syslog message. In the file, this message would be on a single line. This message has the facility name of local7, which is the name used for all Viptela processes, and a priority of "info". Dec 29 16:50:56 vedge DHCP_CLIENT[324]: 
Renewed address for interface mgmt0 

Additional Information

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