Dell PowerConnect 7048P User Manual - Page 274
Why is the System Time Needed?, How Does SNTP Work?, show users login-history
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SDM Template Configuration Guidelines 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. NOTE: 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. 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. Why is the System Time Needed? 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. How Does SNTP Work? 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. 274 Managing General System Settings
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1,190
-
1,191
-
1,192
-
1,193
-
1,194
-
1,195
-
1,196
-
1,197
-
1,198
-
1,199
-
1,200
-
1,201
-
1,202
-
1,203
-
1,204
-
1,205
-
1,206
-
1,207
-
1,208
-
1,209
-
1,210
-
1,211
-
1,212
-
1,213
-
1,214
-
1,215
-
1,216
-
1,217
-
1,218
-
1,219
-
1,220
-
1,221
-
1,222
-
1,223
-
1,224
-
1,225
-
1,226
-
1,227
-
1,228
-
1,229
-
1,230
-
1,231
-
1,232
-
1,233
-
1,234