Policy Framework Configuration Guide - Juniper Networks

Chapter 15: Traffic Forwarding and Monitoring Configuration
To generate a permuted index of next-hop entries for unicast and aggregate next hops,
include the indexed-next-hop statement at the [edit forwarding-options load-balance]
hierarchy level:
indexed-next-hop;
Configuring Per-Flow Load Balancing Based on Hash Values
By default, the Junos OS uses a hashing method based only on the destination address
to elect a forwarding next hop when multiple equal-cost paths are available. All Packet
Forwarding Engine slots are assigned the same hash value by default.
You can enable router-specific or switch-specific load balancing by configuring the router
or switch to assign a unique, load-balance hash value for each Packet Forwarding Engine
slot.
NOTE: This feature is supported only on M120, M320, and MX Series routers.
To configure per-flow load balancing. include the load-balance statement at the [edit
forwarding-options] hierarchy level:
[edit forwarding-options]
load-balance {
indexed-next-hop;
per-flow {
hash-seed;
}
}
To enable per-flow load balancing, you must include the hash-seed statement. The Junos
OS automatically chooses a value for the hashing algorithm. You cannot configure a
specific value for the hash-seed statement when you enable per-flow load balancing.
Configuring Routers, Switches, and Interfaces as DHCP and BOOTP Relay Agents
You can configure the router, switch, or interface to act as a Dynamic Host Configuration
Protocol (DHCP) and Bootstrap Protocol (BOOTP) relay agent. This means that a locally
attached host can issue a DHCP or BOOTP request as a broadcast message. If the router,
switch, or interface sees this broadcast message, it relays the message to a specified
DHCP or BOOTP server.
You should configure the router, switch, or interface to be a DHCP and BOOTP relay
agent if you have locally attached hosts and a distant DHCP or BOOTP server.
To configure the router or switch to act as a DHCP and BOOTP relay agent, include the
bootp statement at the [edit forwarding-options helpers] hierarchy level:
[edit forwarding-options helpers]
bootp {
client-response-ttl number;
description text-description;
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