In a real world network, we are absolutely going to want to optimize our access
layer environment
by performing these configurations on the distribution switch.
The goal is going to be to divide our VLANs up and load balance that way
because we don't
want to block the same link for all of the VLANs or that link will never get
used and
the other one is likely going to get overwhelmed.
So if we have VLANs 10 through 19, we could do an evens and odds kind of split. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So if we have VLANs 10 through 19, we could do an evens and odds kind of split.
So we could say 11, 13, 15, 17 and 19 for the switch on the left and then VLANs
10, 12,
14, 16 and 18 on the right.
This is going to define which VLANs I am the root for and also the FHRP active.
And so whether we're running VRRP or HSRP either way, it's going to be the same
and then
we'll do the same thing over on this side with us having root and active WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
we'll do the same thing over on this side with us having root and active
configured
for these even VLANs.
Now how you split up the VLANs doesn't matter if you did 10 through 14 and 15
through
19, that would be perfectly fine.
Again, our assumption, it's truly an assumption is that every VLAN has about
the same amount
of traffic flowing through it.
If we know that VLANs 17 and 19 are heavier than the rest, then we'd want to
split those
up.
But in this example, we weren't given that information.
So at this point, we will see that the VLANs here, the odd VLANs will block WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So at this point, we will see that the VLANs here, the odd VLANs will block
this link and
then the even VLANs will block the link over here.
And that will mean that the even traffic flows out this way.
I guess from the client side, the even VLANs will flow this way and land on
their own
active.
The odd traffic will flow out this way, land on the SVI for their traffic and
we will be
very efficient here.
So the second apology involves virtual port channels. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
So the second apology involves virtual port channels.
And as we talked about, this means that we have this active, active load-
balanced type
of situation and this completely changes the nature of things.
We don't have STP blocked ports in our environment or at least for this
particular link.
And our FHRP's are running active, active.
And at this point, it doesn't matter whether we're getting sent out this link
or this link,
either way, we're going to be able to get processed and forwarded on. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
either way, we're going to be able to get processed and forwarded on.
And so this is where Cisco changes their recommendations to say whichever one
of these
nodes is the VPC primary.
Let's say it's the one on the left.
At this point, this switch should be configured as the STP root for all of the
VLANs and
the FHRP active for all of the VLANs as well.
So this will be for VLANs 10 through 19.
Now I know we said it's active, active, but we will still see that this node is WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
Now I know we said it's active, active, but we will still see that this node is
running
as the standby node.
The difference is the standby node is able to, again, forward that traffic out.
So it does change things a little bit in the data center.
It's important to be aware of that because as we study FHRP's and when we get
to a spanning
tree protocol, all of that is going to go out to not only our campus
environments, but
also the data center environment as well.
And we need to understand how to deploy that into this type of environment.
I hope this has been informative for you and a light to thank you for viewing.