examen 1 ccna 1

examen 1 ccna 1.Once a network device is configured to log and generate Syslog messages with a significance code of X, it is actually told to log and generate Syslog messages with a significance code less than or equal to X. For example, if you tell a network device (router, switch, firewall) to log Syslog messages with a significance code of debug, it will also log all Syslog messages with a significance code of 0.6.Most Cisco infrastructure devices support the use of Syslog to manage system logs and alarms. Cisco routers or switches log into the console or internal cache, or you can configure these devices to send log messages to an external Syslog server for storage. It is recommended that you let the network device send logs to the Syslog server because the size of the logs that the Syslog server can store is limited only by local disk space and is independent of the resources of the network device. The Cisco network device does not send logs to an external Syslog server without any configuration. Figure H-1 shows a router (R1) configured to send all logs to the Syslog server with IP address 10.8.1.10 within the management network.1. Network Time Protocol and Its ImportanceBefore having Cisco devices (switches, routers, firewalls) send Syslog messages to the Syslog server, make sure they have the correct date, time, and time zone. If the date and time of the Syslog message is incorrect, it will be useless. One best practice is to turn on Network Time Protocol (NTP) on all devices in the network. The main purpose of turning on NTP is to have all devices within the network have the correct time and keep the time synchronized.11.2 Network Insight Technology 397Host A Host B (10.10.10.8) (10.10.20.2)Managing the Network Syslog ServerFigure 11-1 Syslog Server Topology 10.8.1.10 In Example 11.1, the ipname-server command is configured on the router (R1) to allow R1 to perform DNS resolution with the CiscoOpenDNS free DNS server 208.67.222.222; the ipdomain-lookup command has the effect of enable DNS domain lookup for R1; the ntp server command has the effect of making R1 an NTP client that synchronizes time with the NTP server O.north-america.pool.ntp.org.Example 11-1 Cisco Router Configuration Related to NTPRl#configureterminal