3com 5500-ei pwr Installation Instruction

 

2-4 

z 

When you merge two or more XRN systems into one XRN system, a new master unit is elected, 

and the new XRN system adopts new configurations accordingly. This may result in the existing 

system configurations (including the address pools configured for the DHCP servers) being lost. As 

the new XRN system cannot inherit the original DHCP server configurations, you need to perform 

DHCP server configurations for it. 

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When an XRN system is split into multiple new XRN systems, some of the new XRN systems may 

be degraded to Layer 2 devices. For a new XRN system degraded to Layer 2 device, although the 

original DHCP server still exists in the new system, it runs idle for being unable to receive any 

packets. When the XRN system restores to a Layer 3 device due to being merged into a new XRN 

system, it adopts the configurations on the new XRN system. And you need to perform DHCP 

server configurations if the new XRN system does not have DHCP server-related configurations. 

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In an XRN system, the UDP HELPER function must be enabled on the DHCP servers that are in 

fabric state. 

 

Complete the following tasks to configure the DHCP server: 

Required 

Configure address 
pool based DHCP 
server 

One of the two options is 
required 

Configuring DHCP Server Security Functions 

Optional 

Optional 

Optional 

 

You need to enable DHCP to make other related configurations take effect. 

Follow these steps to enable DHCP: 

Enter system view 

— 

Enable DHCP 

Optional 

By default, DHCP is enabled.