DELL N3000 User Manual

Managing General System Settings

When you configure the switch to use an SDM template that is not currently 

in use, you must reload the switch for the configuration to take effect.

If the IPv4 Routing or IPv4 Data Center template is currently in use and you 

attempt to configure IPv6 routing features without first selecting the Dual 

IPv4-IPv6 Routing template, the IPv6 commands do not take effect. IPv6 

features are not available when an IPv4-only template is active.

The switch uses the system clock to provide time stamps on log messages. 

Additionally, some show commands include the time in the command 

output. For example, the show users login-history command includes a Login 

Time field. The system clock provides the information for the Login Time 

field.

SNTP assures accurate switch clock time synchronization. Time 

synchronization is performed by a network SNTP server. 
Time sources are established by Stratums. Stratums define the accuracy of 

the reference clock. The higher the stratum (where zero is the highest), the 

more accurate the clock. The switch is at a stratum that is one lower than its 

time source. For example, if the SNTP server in an internal network is a 

Stratum 3 device, the switch is a Stratum 4 device.
You can configure the switch to request the time from an SNTP server on the 

network, or you can allow the switch to receive SNTP broadcasts. 
Requesting the time from a unicast SNTP server is more secure. Use this 

method if you know the IP address of the SNTP server on your network. If you 

allow the switch to receive SNTP broadcasts, any clock synchronization 

information is accepted, even if it has not been requested by the device. This 

method is less secure than polling a specified SNTP server.

If you attach a unit to a stack and its template does not match the stack's 

template, then the new unit will automatically reboot using the template used by 

the management unit. To avoid the automatic reboot, you may first set the 

template to the template used by the management unit. Then power off the new 

unit, attach it to the stack, and power it on.