Quick Reference Guide

594 PowerConnect B-Series TI24X Configuration Guide
53-1002269-02
Configuring IP parameters – Layer 3 Switches
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NOTE
When you enable the Layer 3 Switch for zero-based subnet broadcasts, the Layer 3 Switch still treats
IP packets with all ones the host portion as IP subnet broadcasts too. Thus, the Layer 3 Switch can
be configured to support all ones only (the default) or all ones and all zeroes.
NOTE
This feature applies only to IP subnet broadcasts, not to local network broadcasts. The local network
broadcast address is still expected to be all ones.
To enable the Layer 3 Switch for zero-based IP subnet broadcasts in addition to ones-based IP
subnet broadcasts, enter the following command.
PowerConnect(config)#ip broadcast-zero
PowerConnect(config)#write memory
PowerConnect(config)#end
PowerConnect#reload
NOTE
You must save the configuration and reload the software to place this configuration change into
effect.
Syntax: [no] ip broadcast-zero
NOTE
This command is not supported on the PowerConnect B-Series TI24X devices.
Disabling ICMP messages
Devices are enabled to reply to ICMP echo messages and send ICMP Destination Unreachable
messages by default.
You can selectively disable the following types of Internet Control Message Protocol (ICMP)
messages:
• Echo messages (ping messages) – The Layer 3 Switch replies to IP pings from other IP devices.
• Destination Unreachable messages – If the Layer 3 Switch receives an IP packet that it cannot
deliver to its destination, the Layer 3 Switch discards the packet and sends a message back to
the device that sent the packet to the Layer 3 Switch. The message informs the device that the
destination cannot be reached by the Layer 3 Switch.
Disabling replies to broadcast ping requests
By default, devices are enabled to respond to broadcast ICMP echo packets, which are ping
requests.
To disable response to broadcast ICMP echo packets (ping requests), enter the following command.
PowerConnect(config)#no ip icmp echo broadcast-request
Syntax: [no] ip icmp echo broadcast-request
If you need to re-enable response to ping requests, enter the following command.
PowerConnect(config)#ip icmp echo broadcast-request