Cisco 2950 - Catalyst Switch User Manual

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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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Chapter 8 Administering the Switch
Managing the System Time and Date
Figure 8-1 Typical NTP Network Configuration
If the network is isolated from the Internet, Cisco’s implementation of NTP allows a device to act as
though it is synchronized through NTP, when in fact it has determined the time by using other means.
Other devices then synchronize to that device through NTP.
When multiple sources of time are available, NTP is always considered to be more authoritative. NTP
time overrides the time set by any other method.
Several manufacturers include NTP software for their host systems, and a publicly available version for
systems running UNIX and its various derivatives is also available. This software allows host systems to
be time-synchronized as well.
Configuring NTP
The switch does not have a hardware-supported clock, and it cannot function as an NTP master clock to
which peers synchronize themselves when an external NTP source is not available. The switch also has
no hardware support for a calendar. As a result, the ntp update-calendar and the ntp master global
configuration commands are not available.
Switch F
Switch A
Workstations
Workstations
Local
workgroup
servers
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Switch B
Switch E
Switch C Switch D

Cisco 2950 - Catalyst Switch Specifications

General

Forwarding Rate	6.6 Mpps
Jumbo Frame Support	No
Weight	8.8 lbs (4 kg)
RAM	16 MB
Flash Memory	8 MB
Manageable	Yes
Form Factor	Rack-mountable
Ports	24 Ethernet 10/100 ports
Uplink Ports	2 x 10/100/1000Base-T ports
VLANs	250
MAC Address Table Size	8000
Power Supply	100-240 VAC, 50-60 Hz
Dimensions	4.4 cm x 44.5 cm x 24.2 cm
Operating Temperature	0 to 40 °C (32 to 104 °F)
Storage Temperature	-25 to 70 °C (-13 to 158 °F)
Operating Humidity	10% to 85% (non-condensing)
Storage Humidity	5% to 95% (non-condensing)