Disabling Icmp Messages - Foundry Networks Switch and Router Installation And Configuration Manual

2. Click on the plus sign next to Configure in the tree view to expand the list of configuration options.
3. Click on the plus sign next to IP in the tree view to expand the list of IP option links.
4. Click on the General link to display the IP configuration panel.
5. Select the Disable or Enable radio button next to Source Route.
6. Click the Apply button to save the change to the device's running-config file.
7. Select the Save link at the bottom of the dialog. Select Yes when prompted to save the configuration change
to the startup-config file on the device's flash memory.
Enabling Support for Zero-Based IP Sub-Net Broadcasts
By default, the Layer 3 Switch treats IP packets with all ones in the host portion of the address as IP broadcast
packets. For example, the Layer 3 Switch treats IP packets with 209.157.22.255/24 as the destination IP address
as IP broadcast packets and forwards the packets to all IP hosts within the 209.157.22.x sub-net (except the host
that sent the broadcast packet to the Layer 3 Switch).
Most IP hosts are configured to receive IP sub-net broadcast packets with all ones in the host portion of the
address. However, some older IP hosts instead expect IP sub-net broadcast packets that have all zeros instead
of all ones in the host portion of the address. To accommodate this type of host, you can enable the Layer 3
Switch to treat IP packets with all zeros in the host portion of the destination IP address as broadcast packets.
NOTE: When you enable the Layer 3 Switch for zero-based sub-net broadcasts, the Layer 3 Switch still treats IP
packets with all ones the host portion as IP sub-net 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 sub-net 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 broadcasts, use either of the following methods.
USING THE CLI
To enable the Layer 3 Switch for zero-based IP sub-net broadcasts in addition to ones-based IP sub-net
broadcasts, enter the following command.
BigIron(config)# ip broadcast-zero
Syntax: [no] ip broadcast-zero
USING THE WEB MANAGEMENT INTERFACE
You cannot enable zero-based IP sub-net broadcasting using the Web management interface.

Disabling ICMP Messages

Foundry 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, Foundry devices are enabled to respond to broadcast ICMP echo packets, which are ping requests.
You can disable response to ping requests on a global basis using the following CLI method.
December 2000
Configuring IP
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