Now for those famous words...."It depends."
In the most basic setup you could have two ISP connections. Use ip
default-network command to establish default routes to both providers. This
would give you either per-packet or per-destination load balancing for
outbound traffic. Inbound traffic would be dependent on the Internet Route
table of the ISPs. Technically you could ask both ISP's to announce
reachability to your network. Real world, your IP subnet block probably
belongs to a larger subnet block of your ISP's so the providers may not want
this to happen.
Here is what we have done for our customers.
We have the customer acquire a BGP AS number and IP subnet (www.arin.net).
You have to talk to the ISP's about running BGP with them. I think it is
better to have 1 router per ISP (3620 full of DRAM. Your routers will
announce reachability for you network to both providers. Both routers
accept full BGP routes and your routers run iBGP. Set up HSRP on the
Ethernet Interfaces (tracking the serial interfaces) facing your LAN
(usually outside int of Firewall). A Crossover Ethernet cable connects the
second Ethernet interface on the routers for the iBGP link.
With this configuration all traffic coming from you LAN will enter the same
router. Depending on the route tables, internal traffic will enter the HSRP
router and then either exit to the Internet or jump to the other router then
exit.
Inbound traffic is harder to control. AS-prepending can be used to make one
path look less desirable than the other. You will probably never get 50%
inbound traffic into router A and 50% in router B.
Alternative...
You may want to ask an ISP for 2 Internet connections coming from 2
different POPs. This will give you some redundancy and save you the hassle
of the BGP stuff. If you go with a larger provider (Qwest, ATT, Sprint,
etc.) The redundancy will be fine.
Let me know if you have more questions.
^-^-^-^-^-^-^-^-^-^-^
Bill Carter
CCIE #5022
^-^-^-^-^-^-^-^-^-^-^
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of
DBates
Sent: Thursday, September 06, 2001 10:59 AM
To: [EMAIL PROTECTED]
Subject: Load Sharing vs Load Balance [7:18821]
Can any one tell me the difference between load sharing and load balancing
?????
I would like my company to use two different ISP connections and load
balance between the two.
Is this a case for BGP ????
Thanks,
Dennis
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=18844&t=18821
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