Alcatel-Lucent 7450 Basic System Configuration Manual page 346

System Command Reference
Description This command configures system-wide Layer 4 load balancing. The configuration at the system level
can enable or disable load balancing based on Layer 4 fields. If enabled, the Layer 4 source and
destination port fields will be included in hashing calculation for TCP/UDP packets.
The hashing algorithm addresses finer spraying granularity where many hosts are connected to the
network.
To address more efficient traffic distribution between network links (forming a LAG group), a hashing
algorithm extension takes into account L4 information (that is, src/dst L4-protocol port).
The hashing index can be calculated according to the following algorithm:
This algorithm will be used in all cases where IP information in per-packet hashing is included (see
LAG and ECMP Hashing in the Interfaces Guide). However, the Layer 4 information (TCP/UDP
ports) will not be used for fragmented packets.
Default no l4-load-balancing
lsr-load-balancing
Syntax lsr-load-balancing {lbl-only | lbl-ip | ip-only | eth-encap-ip}
no lsr-load-balancing
Context config>system>load-balancing
Description
This command configures system-wide LSR load balancing. Hashing can be enabled on the IP header
at an LSR for spraying labeled IP packets over multiple equal cost paths in ECMP in an LDP LSP and/
or over multiple links of a LAG group in all types of LSPs.
The LSR hash routine operates on the label stack and the IP header if a packet is IPv4. An LSR will
consider a packet to be IPv4 if the first nibble following the bottom of the label stack is 4. IPv4 is
supported only and on IOM-3 and IMMs. IPv6 packets are hashed on label stack only. The hash on
label and IPv4 header can be enabled or disabled at the system level only.
Default
disabled
Parameters lbl-only — Only the label is used in the hashing algorithm.
lbl-ip — The IP header is included in the hashing algorithm.
ip-only — the IP header is used exclusively in the hashing algorithm
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If [(TCP or UDP traffic) & enabled]
hash (TCP/UDP ports, IP addresses)
else if (IP traffic)
hash (IP addresses)
else
hash (MAC addresses)
endif
Basic System Configuration Guide