Icmp Tasks - Juniper IGP - CONFIGURATION GUIDE V11.1.X Configuration Manual

JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide
ICMP messages are sent only when errors occur in either the processing of an
unfragmented data packet or the first fragment of a fragmented data packet.
ICMP messages are encapsulated as part of the data portion of an IP data packet and
are routed like any other IP data packets. Thus, there is no guarantee to the sender
of an ICMP message that the message will be delivered to its destination.
The router supports ICMP redirects. When a packet enters an IP interface and exits
the same interface, the router may send an ICMP message to the originator of the
packet. This message notifies the originator that a better gateway exists to the
assigned destination address.
With the ip redirects command (used in Interface Configuration mode) you can
enable or disable ICMP redirects. This attribute is enabled by default. If it is enabled
on the IP interface and if the internal ICMP redirect queue is not full, the router sends
an ICMP redirect packet to the originator. When the originator receives the ICMP
redirect notification, the originator determines whether to start using the better
gateway.

ICMP Tasks

You can enable the following ICMP features:
ip irdp
ip mask-reply
ip redirects
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Internet Control Message Protocol
ICMP Router Discovery Protocol (IRDP)
ICMP netmask reply
Sending of IP redirects
Generation of ICMP unreachable messages
Use to enable IRDP processing on an interface.
Example
host1(config-if)#ip irdp
Use the no version to disable the function.
See ip irdp
Use to enable ICMP netmask reply.
Example
host1(config-if)#ip mask-reply
Use the no version to disable the function.
See ip mask-reply