The primary consideration with this topology challenge is to make sure we
remember that we
perform load balancing in our distribution and access layers, especially
traditional
layer 2 ones, by making sure that our spanning tree roots are split up between
the distribution
switches and we align the FHRP active with those specific switches.
Now normally we would just say all the VLens are about the same traffic so we
're going
to evenly divide them but this challenge did throw a little bit of a curveball WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
to evenly divide them but this challenge did throw a little bit of a curveball
at us.
So let's say again that we're going to set the root to the active on the left
and the
root to the active on the right but we're going to do this for the odd VLens
over here and
the even VLens on the right.
And to some extent that could be the end of our conversation but it was
specifically
called out that VLens 55 and 63 should be split up essentially. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
called out that VLens 55 and 63 should be split up essentially.
It was said that these were the heavy loaded VLens and we don't want both of
them on one
side because that will more heavily load one of the links.
So let's split those up.
But if we're going to split them up then we should probably move one of the
other VLens
over to the odd from the events.
So maybe we just take the very first one and say I'm going to run 50 and 55
which is an
odd and then all the VLens on one side, 63 and all the other VLens besides 50 WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
odd and then all the VLens on one side, 63 and all the other VLens besides 50
on the other.
However you divided this up is largely fine so long as we recognize sort of
what we're
trying to accomplish with the load balancing element.
And the idea here is that now that we have a root and an active on one of these
doesn't
matter which one pick VLens 50 at this point.
Well because of the way spanning tree works I'm going to have a better path
this way than
through the other switch and so I will block this link. WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:900000
through the other switch and so I will block this link.
Same thing with this switch will block this link.
And this will ensure that as traffic comes in destined for the gateway that it
arrives
directly on the active.
If the active was over here then we'd have to go this way to get to it which is
inefficient.
And so we take the most direct path to the gateways and we are ideally load
balancing all
of these links as best we can by dividing up the VLens and also dividing up the
heaviest
loaded ones.