Hi my name she had from teach ethics.
Welcome you all to Cisco firewalls course in this video we will cover the topic of what we call a fail
over.
Cisco is a active stand by fail over by the end of this give you.
You will be able to understand the concept of the active standby fail over.
So let's start as we can see in this figure what we mean by a fail over is to have a secondary or spear
firewall in case the mean firewall fails.
So mainly you have two firewalls connected with a link.
We call it a fail over link in case the main firewall fails despair or what we call a standby firewall
takes over OK.
So the active standby concept enables you enables the use of standby is a to take over the functionality
of a failed one when the active unit fails to change through the stand by state.
So the main one which is it changed its state to stand by state.
We will see how this occurs in the next this light.
Why the standby one which is the spare one.
It changed its state to the active state All right so let's see how this occurs.
Then you need that becomes active assumes the IP address or in the case of that transparent firewall
which we discussed in an earlier video.
It assumes the management IP address and the management interface ip address and Mac ads so mainly when
the Fed when the standby firewall takes over the main one takes over the active one it takes its IP
address and MAC address OK all right.
So now if the secondary unit which is the fail over unit or the stand by unit if it boots without detecting
the primary unit if if we assume that below one is the stand by one if it puts and doesn't detect that
MAC address of the primary over the active one it becomes immediately the active one it becomes the
active unit and uses its own MAC address OK.
So the MAC address will be changed if we use its own MAC address instead of the active firewall MAC
address OK.
All right.
So what if the primary or the active standby becomes active again if the primary unit or the active
unit becomes available.
The standby or the secondary active unit.
It changed the MAC address to the primary one so if the active one becomes available again the standby
unit will use the active well or MAC address so it will change its MAC address which is the own one
that it has already it will change to the primary fire all my characters.
OK.
So let's clear this if the fail over firewall boots and doesn't take the mic address of the active one
it use its own its is the active one becomes available again.
Stand by one would change its mac address to the MAC address that was used by the active fire.
OK all right let's see the next slide here.
All right what do we need to apply or deploy the active standby field over concept we need actually
two identical appliances they have to be identical.
The model has to be the same.
OK how we connected.
We connect them through actually a cable we call a fill over cable
and the link between them.
It's called we call it Cisco cause it failed over link.
We will see actually how this looks like in the next slide.
All right.
So the health of the active interface which is this one is monitored.
That is continuous monitoring of the health of the active firewall.
If some specific conditions are met which means if the health of the active firewall actually got impacted
by something if those conditions are met the Phil overall is SO THE STAND BY ONE WILL TAKE OVER OK so
there is two actually cases or two configurations of the active standby field over either both firewalls
are active which means both are active state in this case there would be a load balancing on the network
so they would load bats because both are active if one is active and wouldn't stand by one firewall
being active if it feeds the standby one with the so active active an active standby OK now it looks
like these are two firewalls connected with a fit over cable as you can see here the lead here for the
active firewall is green which means it's an active state the stand by one.
Actually it's not with a second
it's move this over here
as you can see it's not green which means it's in standby state.
So when this phase the active one the below one will take over.
OK so two identical firewalls connected.
One is active.
One is stand by when this phase this one takes over that's all for this video in the next video we will
discuss the topic of what we call a visual aids a firewall.
Hope you enjoy the view.
Thank you for watching.