Multi Level Cluster
What is Multi-Level Cluster?
A cluster which has different regions is called Multi-Level Cluster where each region has its own origin for a stream. Ant Media Server can be scaled in different physical locations. You can set the node group parameter of the servers to create regions. Separating the nodes into regions based on their physical location has some advantages in performance and data-transfer. Because each region will have their own origin node for a stream, the edges in a region will pull the stream from the origin of their region.
How does it work?
Let's clarify the the case with an example scenario. We have two scenarios
- Publisher & Players in the same cluster
- Publisher & Players in the different clusters
Let's remember the traditional scenario
Publisher & Players in the same cluster
Publisher
starts a stream and it is assigned to theOrigin1
instance in theRegion1
Player1
who is close toRegion1
instance requests to play the stream.Player1
is assigned toEdge11
instance to receive the stream inRegion1
- Since the
Origin1
is the origin of the stream,Edge11
will pull stream fromOrigin1
.
Publisher & Players in the different clusters
Player2
who is close toRegion2
requests to play the stream.Player2
is assigned toEdge21
instance inRegion2
Edge21
checks the origin of the stream.- Since there is no origin instance in
Region2
to play the stream. It assigns itself as the secondary origin for that stream inRegion2
. Edge21
pulls the stream from theOrigin1
(main origin) inRegion1
.Edge21
sends the stream toPlayer2
.
- Since there is no origin instance in
Player3
who is close toRegion2
requests to play the stream.Player3
is assigned toEdge22
inRegion2
.Edge22
checks the origin of the stream. SinceEdge21
is a secondary origin for the stream in theRegion2
, it pulls the stream fromEdge21
and serves toPlayer3
.
In short, each stream is distributed from single node in each region even if they are in different regions.
How to configure Multi-Level Cluster?
You can set the node group (or region) of a server by adding nodeGroup=GROUP_NAME
in conf/red5.properties
file. Make sure that the instances running in the same region should have the same nodeGroup
value
Keep in mind that you should configure the Load Balancer to forward Publish and Play requests to the best region. If you have a global cluster in different geolocations, you should have a Load Balancer like Route53.