3Com 100 TX manual Power-Up Disabled Option Switch, Enabled

Power-Up Disabled Option Switch 3-13

Power-Up

Disabled Option

Switch

If network management is present, an external switch on the hub’s rear panel allows you to power-up the hub with the ports disabled. The power-up disabled option switch is located between the expansion connectors and the DC input connector, as shown in Figure 3-12.

This feature cannot be fully implemented unless a network management device (such as the LinkBuilder FMS 100 Management Unit) is connected to the hub stack. If no network management is present, leave the power-up disabled option switch in the enabled position (set to E).

tion	EXPA
A

	DC INPUT		UP
–12	D	E	DOWN
0.2
			Power-up disabled
			option switch

Figure 3-12 Power-Up Disabled Option Switch

Table 3-4 describes the functioning of the power-up disabled option switch.

Table 3-4 Settings on Power-Up Disabled Option Switch

Setting	Result
D (disabled)	If network management is present, you can enable specific ports
	after the hub has been powered-up.
	If network management is not present, all ports remain disabled
	after the hub has been powered-up.
E (enabled)	This is the default setting. All ports are enabled after the hub has
	been powered-up, whether or not network management is present.
	If network management is present, individual ports can then be
	disabled after the hub has been powered-up.

You can use this option for security purposes. For example, you can disable a port where a faulty device or other problem exists. This prevents the disabled port from receiving any data when the hub is powered-up. Conversely, you can enable ports if you want them to receive data.