HP 2920 Series User Manual

Forwarding for all types of IP directed broadcasts is disabled by default. You can enable forwarding
for all types if needed. You cannot enable forwarding for specific broadcast types.
Enabling forwarding of IP directed broadcasts (CLI)
To enable forwarding of IP directed broadcasts, enter the following CLI command:
HP Switch(config)# ip directed-broadcast
Syntax:
[no] ip directed-broadcast
HP software makes the forwarding decision based on the routing switch's knowledge
of the destination network prefix. Routers cannot determine that a message is unicast
or directed broadcast apart from the destination network prefix. The decision to
forward or not forward the message is by definition only possible in the last-hop
router.
Disabling the directed broadcasts
To disable the directed broadcasts, enter the following CLI command:
HP Switch(config)# no ip directed-broadcast
Configuring ICMP
You can configure the following ICMP limits:
The maximum number of ICMP replies to send per second.Burst-normal
You can enable or disable ICMP reply rate limiting.Reply limit
Disabling ICMP messages
HP 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:
The routing switch replies to IP pings from other IP devices.Echo messages (ping
messages)
If the routing switch receives an IP packet that it cannot deliver to its destination, the
routing switch discards the packet and sends a message back to the device that sent the
Destination unreachable
messages
packet to the routing switch. The message informs the device that the destination cannot
be reached by the routing switch.
You can enable or disable ICMP address mask replies.Address mask replies
Disabling replies to broadcast ping requests
By default, HP devices are enabled to respond to broadcast ICMP echo packets, which are ping
requests (for more information, see “Disabling ICMP messages” (page 44)).
To disable response to broadcast ICMP echo packets (ping requests), enter the following command:
HP Switch(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:
HP Switch(config)# ip icmp echo broadcast-request
44 IP Routing Features

HP 2920 Series Specifications

General

Brand	HP
Model	2920 Series
Category	Switch
Language	English