This excerpt from the manual should answer your question:
JUNOS Routing and Routing Protocols v5 Manual, page 126
... snip snip ...
On routers with the Internet Processor II ASIC, when per-packet load
balancing is configured, traffic between routers with multiple paths is
divided into individual traffic flows (up to a maximum of 16 equal-cost
load-balanced paths). Packets for each individual flow are kept on
a single interface. To recognize individual flows in the transit
traffic, the router examines each of the following:
! Source IP address
! Destination IP address
! Protocol
! Source port number
! Destination port number
! Interface through which the packet entered the router
... snip snip ...
The new tag offered in JUNOS 5.0 called "load-balance per-flow" simply
allows you to modify the behavior already enabled with the "per-packet"
tag. More specifically, it allows you to determine what defines a flow:
layer 3 information (IP) or layer 4 information (TCP/UDP).
As a side note, the manual does not state what the *actual* algorithm is
for path selection. If anyone knows it would be nice to hear.
Predicting which interface a flow will pass through could come in handy.
(something like XOR of all variables listed above and the # of equal
cost paths?)
-- steve
-----Original Message-----
From: Andrew Smith [mailto:as160@yahoo.com]
Sent: Thursday, October 18, 2001 12:45 AM
To: juniper-nsp@puck.nether.net
Subject: Per packet load balancing
Hi, all
I have a question regarding this.
If I've enabled per-packet load balancing for all
routes. Assuming IP2 in this case. As stated on the
doc:
"
user@host# set policy-options policy-statement
load-balancing-policy then load-balance per-packet
user@host# set routing-options forwarding-table export
load-balancing-policy"
Assume I have 4 equal cost links for 8 destinations.
With the above config, will each link carry the same
number of destinations? (i.e. 2 destinations per
link)
What determines which destination is assigned to which
link?
I know you could achieve this by using filtering,
however, I like to know what is the default behavior
is.
TIA
---andrew
__________________________________________________
Do You Yahoo!?
Make a great connection at Yahoo! Personals.
http://personals.yahoo.com
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com
This archive was generated by hypermail 2b29 : Mon Aug 05 2002 - 10:42:37 EDT