You have issued the logging enable command on an ASA with the default configuration.
Which of the following statements is true regarding the syslog messages that will be generated on this ASA by default? (Select the best answer.)
- The ASA will generate syslog messages that include a date.
- The ASA will generate syslog messages that include a time.
- The ASA will not generate syslog messages with a severity of 0.
- The ASA will not generate syslog messages with a severity of 7.
- The ASA will send syslog messages to only the console.
A Cisco Adaptive Security Appliance (ASA) with a default configuration and logging enabled will not generate system log (syslog) messages with a severity of 0. This value correlates with the severity of the event that caused the message to be generated? higher values indicate a less severe event. Level 0 is an emergency severity level and denotes that the system is unusable. Although an ASA will not generate syslog messages with a severity level of 0, severity level 0 is supported on the ASA to ensure compatibility with the UNIX syslog feature. The following table lists the syslog severity levels that can be generated by an ASA:
When an ASA is configured to direct syslog messages to a specific output location, it will include all messages with a severity level value less than or equal to the severity level value configured for that particular location. For example, if an ASA is configured to output syslog messages with a severity of 7 to the console, the ASA will also output syslog messages with a severity less than 7 to the console. Therefore, the higher the severity level configured on the ASA, the more syslog messages generated and transmitted to the configured logging destinations.
An ASA with a default configuration and logging enabled will not send syslog messages to only the console.
Although syslog messages for all supported severity levels are generated once logging has been enabled, they are not directed to a destination until an output location has been configured on the ASA. Syslog messages can be directed to several different locations, including the ASA’s console port? a syslog server? a Simple Network Management Protocol (SNMP) server? an email address? or a remote session, such as a Telnet session, a Secure Shell (SSH) session, or a Cisco Adaptive Security Device Manager (ASDM) session. When configuring a target location for syslog messages, you must also specify the severity level for the syslog messages that should be directed to the target location. Because directing syslog messages to the console can degrade system performance, Cisco recommends configuring the internal buffer as a destination for syslog messages and then using the show logging command to manually view the buffered messages.
An ASA with a default configuration and logging enabled will not generate syslog messages that include a date or time. Although the timestamp is not included by default, you can configure the syslog to include a timestamp by issuing the logging timestamp command. In addition, you can configure the syslog to include a device ID by issuing the logging deviceid command. The syntax for the logging deviceid command is logging deviceid [contextname | hostname | ipaddress interfacename | string text].