Ip Shared Interface Statistics; Subscriber Interfaces; Internet Control Message Protocol - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - IP-IPV6-IGP CONFIGURATION GUIDE 2010-10-31 Configuration Manual

Example

IP Shared Interface Statistics

Subscriber Interfaces

Internet Control Message Protocol

Copyright © 2010, Juniper Networks, Inc.
does not affect interface statistics, packets forwarded through the interface, or policies
attached to the IP interface.
The following commands create shared interface si0 on the layer 2 interface atm5/3.101:
host1(config)#virtual-router vr-a:vrf-1
host1:vr-a:vrf-1(config)#interface ip si0
host1:vr-a:vrf-1(config-if)#ip share-interface atm 5/3.101
host1:vr-a:vrf-1(config-if)#exit
The following commands move shared interface si0 to the layer 2 interface atm5/3.201:
host1:vr-a:vrf-1(config)#interface ip si0
host1:vr-a:vrf-1(config-if)#ip share-interface atm 5/3.201
Each shared interface has its own statistics. Packets transmitted on a shared IP interface
are always counted only in the shared IP interface.
A subscriber interface is an extension of a shared IP interface. Shared IP interfaces are
unidirectional—they can transmit but not receive traffic. In contrast, subscriber interfaces
are bidirectional—they can both receive and transmit traffic.
For details about configuring and using subscriber interfaces, see JunosE Broadband
Access Configuration Guide.
IP was not designed to provide reliable delivery service. The higher-layer protocols that
operate as clients of IP implement their own reliability procedures if reliable
communications are required.
Internet Control Message Protocol (ICMP) provides a mechanism that enables a router
or destination host to report an error in data traffic processing to the original source of
the packet. ICMP messages provide feedback about problems that occur in the
communication environment.
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
Chapter 1: Configuring IP
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