MACROMEDIA FLASH MEDIA SERVER 2-USING FLASH MEDIA SERVER EDGE SERVERS Use Manual

Brand: MACROMEDIA

Model: FLASH MEDIA SERVER 2-USING FLASH MEDIA SERVER EDGE SERVERS

Type: Use Manual

This manual is also suitable for

FLASH MEDIA SERVER 2

MACROMEDIA FLASH MEDIA SERVER 2-USING FLASH MEDIA SERVER EDGE SERVERS offers enhanced security, flexible scalability, and efficient bandwidth utilization. It enables you to run Flash Media Server applications remotely on edge servers, providing a secure connection point for clients and reducing the load on the origin server. Edge servers authenticate users, authorize requests, and aggregate connections, improving performance and scalability.

Using Flash Media Server

Edge Servers

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Acknowledgments

Project Management: Suzanne Smith

Writing: John Norton, Suzanne Smith

Editing: Evelyn Eldridge, Mary Ferguson, Lisa Stanziano, Anne Szabla

Production Management: Adam Barnett

Media Design and Production: Aaron Begley, Paul Benkman, John Francis, Mario Reynoso

First Edition: October 2005

Macromedia, Inc.

601 Townsend St.

San Francisco, CA 94103

Contents

Using Edge and Origin Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Introducing edge servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

How edge servers work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Caching data in edge servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Deploying edge servers in the DMZ . . . . . . . . . . . . . . . . . . . . . . . . . .9

Explicit and implicit proxies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Reverse proxies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11

Routing information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Connecting to an edge server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Detecting the presence of proxy servers . . . . . . . . . . . . . . . . . . . . . 13

Chaining edge servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Configuring edge servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Deploying a cluster of edge servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Connecting to a cluster of edge servers. . . . . . . . . . . . . . . . . . . . . . 16

Enrolling proxy servers in the cluster . . . . . . . . . . . . . . . . . . . . . . . . 16

Accessing applications through an edge cluster . . . . . . . . . . . . . . 16

Clustering reverse proxies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Setting up origin and proxy servers . . . . . . . . . . . . . . . . . . . . . . . . . 18

Maintaining edge server clusters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Clearing the edge server cache . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

4Contents

Using Edge and Origin

Servers

This chapter describes the various strategies for deploying Flash Media Server with edge and

origin servers.

Introducing edge servers

Until this release of Flash Media Server, clients always connected directly to the computer

where the application was running. These applications were running locally, since their

execution occurred on the same computer that the clients were connected to. This release of

Flash Media Server introduces the concept of remote execution of applications. Flash Media

Server can now run applications locally as an origin server or remotely as edge servers. Edge

servers are not a different kind of Flash Media Server, rather, they are configured to run

applications remotely.

Deploying edge servers in your organization offers significant benefits. Enhanced security is

one benefit. Applications running on the origin server are no longer directly exposed to the

Internet. All requests for Flash Media Server services are routed through known and secure

connection points. These connectors are called edge, or proxy, servers; the terms are

interchangeable. Administrators can monitor the traffic on edge servers. The access log files

for each edge server lets administrators verify that the connections are authorized. The log files

also identify unauthorized requests for connections.

The edge server-origin server deployment is flexible. Edge servers let administrators scale up

or redistribute access to Flash Media Server without dismantling their current deployment.

Administrators can add edge servers. Administrators can reallocate edge servers to match

realignments of users and sites within an organization, or changes in the flow of traffic among

the sites.

6 Using Edge and Origin Servers

Deploying edge servers lets administrators distribute the incoming connection requests for

Flash Media Server services. Traffic between clients and the origin server uses the existing

bandwidth and system resources more efficiently. More traffic occurs locally between the

clients’ computers and the edge server. Without edge servers, all clients have to connect to a

Flash Media Server origin server, no matter where that server is located.

Edge servers mediate communications traffic between the organization’s trusted network and

an untrusted network such as the Internet. Using edge servers does not remove the need for a

firewall to manage the traffic at an IP level, but does provide an additional layer of security at

the application level.

How edge servers work

With an edge-origin deployment strategy, all connection requests from users’ computers for

Flash Media Server services are redirected to an edge server. The edge server receives the

request from the user’s computer, but the edge server is not running the application. The edge

server makes the connection to another computer, called the origin server, where the

application is running. When the origin server fulfills the request for Flash Media Server

services, it sends the application’s data back to the edge server, which in turn forwards the data

to the client (the user’s computer).

It may seem to the users that they are directly connected to the origin server where the

application is located. The edge server does make it appear as if it is running the application.

The edge server’s role, however, is to mediate the communications between clients and the

origin server. Edge servers authenticate the users and authorize their requests for web services.

For example, when Flash Media Server is deployed solely on one computer and is running just

one application instance, system and network resources may not always be sufficient when a

large number of users in an organization want to connect almost simultaneously to Flash

Media Server from multiple locations. Such might be the case in an enterprise-wide meeting

or conference. When too many users want to access the same application at the same time, the

existing bandwidth and system resources can be overwhelmed. Increased latency is another

indication that resources need to be reconfigured or reallocated.

Every connection into the origin server consumes resources independent of the actual data

flowing through the connection. As the number of connections increase, this load can become

inordinately large and adversely affect the server performance. The edge server greatly

mitigates this problem by aggregating connections. The edge multiplexes the connections

from a large number of clients on to one connection to the origin server.

Introducing edge servers 7

Such constraints may prompt the Flash Media Server and network administrators to consider

a different deployment strategy. The strategy involves configuring Flash Media Server to

redistribute the load on system and bandwidth resources by running some virtual hosts as

edge servers and other virtual hosts as origin servers.

Rather than forwarding every request to the origin server and consuming resources for such

repetitive tasks, the edge server collects the requests from a large number of clients and

aggregates them into one connection to the origin server. All communications between edge

and origin servers happen transparently to the users.

To distribute the demands on network and system resources, administrators can assign the

users in a geographical region or functional area of the organization to a specific edge server.

For example, one edge server might aggregate and forward requests from users in Tokyo and

another might aggregate and forward requests from Paris. The edge servers in Paris and Tokyo

gather the requests from their clients and forward them to the origin server located in another

secured location, such as Chicago.

Edge Server

Tokyo

Edge Server

Paris

Origin Server

Chicago

End User

8 Using Edge and Origin Servers

Users in these zones always access the origin server through their assigned edge servers. These

edge servers receive the responses from the origin server, then distribute them back to the

clients (the users’ computers) in their respective zones: Paris or Tokyo. The edge also stores the

data received from the origin server in a cache, and makes it available to other clients that

connect to this edge server. Recycling the data is one more way that edge servers use resources

efficiently. Caching static content reduces the overall load placed on the origin server.

A networked Flash Media Server deployment involves multiple edge servers; these can be

deployed individually or in clusters. Edge servers can also be chained, where one edge server

collects and aggregates the connection requests from other edge servers and their clients, then

transmits the requests to an origin server.

Origen

Server

Client (Users)

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Edge

Server

Client (Users)

Client (Users

)

Client (Users)

Introducing edge servers 9

Caching data in edge servers

An edge server is designed to intercept the requests for Flash Media Server services from users

in a particular zone, collect or aggregate these requests, and transmit them to the origin server.

The origin server returns the results to the edge server, which in turn sends the data back to

the user’s client computer. The edge server also stores this information in its cache, where

other users or clients assigned to the same edge server can access it. In this scenario, fewer

requests for services are forwarded to the origin server.

The edge server caches data such as video streams and shared objects. When a user requests

data that is found in the edge server’s cache, it returns the data to the requesting client (the

user’s computer) without ever calling upon the origin server. This detour is transparent to the

user. The edge server is conserving bandwidth by not connecting to the origin server. In this

scenario, no demands are placed on the origin server.

Deploying edge servers in the DMZ

Edge servers may be deployed in the demilitarized zone (DMZ) of a corporate network. A

DMZ is an isolated network placed between an organization’s trusted network and the

Internet’s untrusted network. In this deployment, the edges function as proxy servers for all

Real Time Messaging Protocol (RTMP) traffic that flows through the organization’s network.

Deploying edge servers in the DMZ provides one more layer of defense between the user’s

Internet connection and the origin server. All traffic that comes from the Internet with Flash

Media Server as its destination must pass through an edge server.

10 Using Edge and Origin Servers

With the edge servers sitting in the DMZ, the network operators can open access to port

1936, avoiding the system overhead and risk of HTTP tunneling. Because the edge server

performs stream splitting and stream caching, it uses the connection to the origin server

efficiently, reducing the Internet bandwidth cost. The user also benefits from the more reliable

connectivity.

Explicit and implicit proxies

Edge servers are defined by the values in the configuration files. Both explicit and implicit

(also called anonymous) proxies intercept and aggregate the clients’ requests to connect to the

applications running on an origin server. The explicit edge server prefixes its address to the

origin server’s Uniform Resource Identifier (URI). This configuration makes the client (the

user’s computer) aware of the proxy. The URI in the explicit proxy specifies the edge servers

that will intercept the clients’ connection requests to the origin server.

The identity (the IP address and port number) of the implicit proxy is hidden from the client.

The implicit proxy does not change or modify the routing information in the incoming URI

before it connects the clients to the origin server. Edge servers are also defined as implicit

proxies through the Flash proxy auto-detection process (FPAD).

Flash Media Server and network administrators can deploy Flash Media Server and route the

incoming connection requests to the origin server through one or more edge servers. These

implicit edges are transparent because the client is unaware of the proxy. They are also

sometimes referred to as interception proxies. This deployment strategy is useful to ISP and

telco providers for optimizing the flow of RTMP traffic through their networks.

Firewall,

Router,

Load Balancer

Edge Server Cluster

80,

443,

1935

Origin

Server

DMZ

443

1935

1936

End User

Introducing edge servers 11

Administrators can explicitly specify that any connection request to an origin server be

automatically routed through an edge or proxy server. For example, if your applications are

running on fms.foo.com, you can redirect the connection request from the users’ computers

to another server (or virtual host) called fmsproxy.foo.com

, which is configured to run in

remote

mode.

Instead of making the usual connection to the applications with the following connection

string:

rtmp://fms.foo.com/app/inst

the clients are redirected through the edge, which prefixes its protocol and hostname to an

existing URI:

rtmp://fmsproxy.foo.com/?rtmp://fms.foo.com/app/inst

The prefix contains only the protocol, hostname, and optionally the port number. The URI

must always end with a trailing slash. A question mark (?) separates the proxy’s prefix from the

main URI.

Reverse proxies

Sometimes you cannot configure the client (as is the case with mobile phones and devices) to

send their connection requests for Flash Media Server services through an edge or proxy

server. In these cases you might set up one or more reverse proxy servers and position them

closer to the origin server. Reverse proxies are usually located within an organization’s DMZ

and control access to Flash Media Server resources from clients connecting through the

Internet to an origin server located behind the firewall. Reverse proxies redirect incoming

connection requests instead of outgoing connection requests as in the case of explicit and

anonymous proxies.

The reverse proxy intercepts all connection requests that arrive from clients, as well as any

edge servers positioned on the outer side of a firewall, authenticates these requests, and then

forwards them to the origin server. The origin server is always located on the inner side of the

firewall. With a reverse proxy, you limit the access to an origin server on the trusted network.

The reverse proxy blocks all traffic except what its configuration allows for. A reverse proxy

also blocks any attempt to access other servers and their resources on the trusted network.

A reverse edge server hides the presence and location of the origin server. Administrators can

explicitly determine that connection requests to Flash Media Server be automatically routed

through a reverse edge or proxy server. You can use RTMPS to configure a reverse proxy to

listen on port 80 for non-secure connection requests and port 443 for secure requests.

12 Using Edge and Origin Servers

For example, if your applications are running on fms-secure.foo.com, you can direct the

connection requests from clients’ devices or computers to the proxy server (or virtual host)

called fms.foo.com

, which makes the connection to fms-secure.foo.com, where your

applications are running. The client is not aware that its request is being sent to another

server.

Routing information

The Flash Media Server or network administrator specifies the routing information for a

proxy or edge server in the

RouteEntry tags of the Vhost.xml configuration file.

Administrators use the Vhost.xml file to configure how and where to route connections to the

desired destination.

The

protocol attribute in the RouteEntry tag specifies the protocol of the outgoing

connection. This attribute must be set to either "rtmp" or "rtmps" to indicate a nonsecure or

secure connection.

The

RouteTable container tag holds all the RouteEntry tags. For example, the RouteTable

container may hold one

RouteEntry tag to specify a secure outgoing connection by using

RTMP, and another

RouteEntry tag that specifies the nonsecure RTMP connection. If a

protocol is not specified, the outgoing connection uses the same protocol as the incoming

connection.

For detailed information on these routing tags, see “Vhost.xml file” in Managing Flash Media

Server.

Connecting to an edge server

Clients can explicitly connect to a specific edge server when they know it is available. You use

a URI in a wrapped format to make the connection to an explicit proxy:

rtmp://edge/?rtmp://origin/app

You can also connect to a chain of proxies by forming a string that routes the outgoing

connection requests through a sequence of explicitly identified proxies:

rtmp://edge1/?rtmp://edge2/?rtmp?://edge3/?rtmp://edge4/?rtmp://origin/app

As the connection moves through each edge in the chain, Flash Media Server drops the first

token in the string. After making the connection to

edge1, the connection string changes to:

rtmp://edge2/?rtmp?://edge3/?rtmp://edge4/?rtmp://origin/app

Introducing edge servers 13

Detecting the presence of proxy servers

Flash Player 8 automatically detects any edge servers in its proximity. When an edge server is

available, Flash Player automatically routes the connection from the client to the origin server

through the proxy server. These edge servers are defined as implicit proxies since the client is

generally unaware that its communication with Flash Media Server is being routed through a

proxy. This use of an implicit proxy allows your current applications to continue working

without any changes. Flash Player exposes the proxy information to the client only through

the read-only properties on the NetConnection object.

For more information on the NetConnection class, see the Client-Side Media ActionScript

Language Reference.

Chaining edge servers

You can chain together any number of edges when you make connections to the origin server.

The following URI shows how two explicit proxies are chained together to direct connection

requests to the origin server:

rtmp://proxy1/?rtmp://proxy2/?rtmp://origin/app/inst

When you use URL decoration to chain proxies, Flash Player 7 and earlier versions may have

problems with shared objects because of the embedded question mark (?) character in the

URL.

A workaround is available for clients who use earlier versions of Flash Player. You can resolve

the problem by using the following function to escape the question marks from the URI

before passing the URI to the shared object.

function escapeURI(uri) {

index = uri.indexOf(‘?’);

if (index == -1) return uri;

prefix = uri.substring(0, index);

uri = uri.substring(index);

return prefix += escape(uri);

}

You call this function on the URI you are about to pass into the shared object, then use the

result of the function instead of the original URI. Flash Player 8 resolves this problem for

Flash Media Server.

NOTE

Earlier versions of Flash Player cannot automatically detect edge servers in their

proximity.

14 Using Edge and Origin Servers

A second problem surfaces when RTMPT is specified in the URI. You may specify this

protocol only for the first prefix. The following are valid URIs:

rtmpt://foo/?rtmp://bar/app/inst

rtmpt://foo:443/?rtmp://bar/app/inst

The following are invalid URIs:

rtmpt://foo/?rtmpt://bar/app/inst

rtmp://foo/?rtmpt://bar/app/inst

Configuring edge servers

All Flash Media Server functionalities—live streaming, on-demand streaming, messaging,

shared object handling, scripting—take place as application instances. Application developers

write scripts to create Flash Media Server applications, instances of which are then distributed

by the Flash Media Server. A minimal application runs on the edge to perform connection

aggregation, stream splitting, stream caching, and smart state management. This separation of

tasks off loads to the edge server a large portion of the processing from the main application

that runs on the origin server.

Flash Media Server and network administrators can configure edge servers to function in

different ways. The XML configuration files define how the edge servers connect clients to the

origin server. These settings determine how the incoming URLs are routed between the edges

and the origin server. You can have a computer run Flash Media Server in a mixed mode, in

which certain virtual hosts on this system run applications locally, while others run

applications remotely.

To configure Flash Media Server, you edit or modify the XML tags in its configuration files.

Following are some representative examples:

■ The Anonymous tag in the Vhost.xml file configures the edge server as either an implicit

(transparent) or explicit proxy.

For more information, see “Anonymous” in Managing Flash Media Server.

■ The Mode tag in the Vhost.xml file configures Flash Media Server to run as an origin or

edge (proxy) server.

For more information, see “Mode” in Managing Flash Media Server.

■ The LocalAddress tag in the Vhost.xml file allows the administrator to control the

network traffic by isolating incoming and outgoing traffic to separate network interfaces.

For more information, see “LocalAddress” in Managing Flash Media Server.

■ The Scope tag in the Application.xml file determines the process scope in which to run

the application. Set this tag to run the applications and proxies in inst mode. Each

application and virtual host has its own process.

For more information, see “Scope” in Managing Flash Media Server.

Introducing edge servers 15

You can find examples of the configuration files, their tag structures, detailed information

about the tags, including cross references to associated tags, syntax, and examples in

Chapter 3, “Configuration Files” in Managing Flash Media Server.

Deploying a cluster of edge servers

You can also deploy a group of connected edge servers as a cluster. Each edge server in a cluster

can access the origin server. Clustering lets you distribute across the many edges in the cluster

all connections to applications that are running on the origin server. The origin server always

remains secure behind the edge servers.

For example, Organization A deploys a cluster of edge servers on its internal network. The

edge servers are defined as explicit proxies and dedicated to service specific users. When the

clients or users want to connect to the origin server, the client first connects to one of the edge

servers in the cluster. It is at this point where the connection requests are authorized or

rejected. If the request is valid, the edge server makes the connection to the origin server,

where the application is running. The origin server returns the results to the edge server,

which passes them on to the requesting client. The edge server also stores the results in a

cache, making it available to other servers and clients.

As this organization grows or reallocates its resources, it can add more edge servers to the

cluster or explicitly reassign clients to different edge servers.

Organization B uses a cluster of edge servers to manage the inbound traffic from clients

located outside of the network. This traffic is destined for Flash Media Server applications

running on the origin server. When these users try to connect to the origin server, a load

balancer positioned before the cluster routes the client’s request to one of the edge servers. The

edge server makes the connection to the origin server, where the application is running. The

clients remain unaware of the presence of the edge servers. The origin server returns the results

to the edge server, which in turn passes them to the requesting client. The edge server also

stores the results in a cache, making it available to the other external clients.

In this scenario, connections to applications are distributed across the many edge servers in

the cluster. If one edge server in the cluster cannot access an application, another edge in the

cluster handles the connection. Applications on the origin server are never directly exposed to

connection requests coming through the Internet.

This scenario describes how Organization B uses a reverse proxy to service incoming

connections instead of outgoing connection, as was the case in the Organization A scenario.

16 Using Edge and Origin Servers

Connecting to a cluster of edge servers

When edge servers are configured into a cluster, the clients probably do not know that edge

servers are present and servicing their connection requests. This is a secure and desirable

strategy for disguising the address of the origin server. A different scheme for connecting

clients to Flash Media Server is required.

With a cluster of proxies in place, when the client attempts to connect to Flash Media Server,

the call to the

NetConnection.connect() method uses the User Datagram Protocol (UDP)

to initiate a local broadcast of an FPAD message. The other edge servers in the network that

receive the FPAD message respond to the client. The client automatically chooses the edge to

connect to. The edge then makes the connection to the origin server. This brief scenario

describes how a cluster of explicit proxies services outgoing connections to an origin server

Enrolling proxy servers in the cluster

Each proxy or edge in a cluster is dynamically assigned a numeric ID when it starts up. The

edge broadcasts a message announcing its presence. All edges in the cluster that are currently

running receive this message. Each edge responds with a message indicating its ID. The ID is

assigned from a sequence of numbers: 0, 1, 2, …, N-1, where N is the number of edges

allowed in the cluster.

The edge that is starting up waits for all of the responses to be received, then assigns itself the

first ID not found in the sequence. When an edge server shuts down, it broadcasts a message

announcing its exit from the cluster.

Accessing applications through an edge cluster

To maximize the conservation of network and bandwidth resources, Flash Media Server

directs to the same edge in a cluster all clients that request a connection to an application. All

the edge servers in the cluster automatically compute an affinity value based on the URI that

the client wishes to connect to. When a client broadcasts an auto discovery process message to

discover the available edges, an affinity value is returned in a message back to the client. After

the client receives responses from all of the currently active edges in the cluster, it

automatically selects the edge with the lowest affinity value to connect to.

The affinity value is dynamic; it adjusts to the increasing or decreasing workload of

connection requests and distributes the workload across edges in the cluster. For instance,

consider how the notion of affinity value applies in a cluster of three edges: edge0, edge1, and

edge2. As the workload on edge0 starts to peak, its connections start to spill over to edge1.

Both have a computed affinity value of 1. As edge1's load increases, its connections start to

spill over to edge2. Both have a computed affinity value of 2. As edge2's load increases, its

connections start to spill over back to edge0.

Introducing edge servers 17

When the load on an edge starts to scale down, so does its affinity value. Because the client

always looks to connect to the edge with the lowest affinity value, this edge begins to take

back connections that had spilled over into the next edge. The objective is to balance the

number of connection requests to the available resources, and have all connections to the same

application instance again pass through the same edge.

The client logic remains simple: to connect to the edge with the lowest affinity value. The

client only needs to know the affinity value for the different edges in the cluster to make the

connection to the right edge.

Clustering reverse proxies

Reverse proxies are configured to redirect incoming connection requests instead of outgoing

connection requests, as is the case with explicit and anonymous proxies. The client’s request to

connect to the desired application must first pass through the load balancer positioned before

the cluster of reverse proxies before it reaches the origin server. When reverse proxies are

deployed, the client's broadcast for a connection request cannot reach either an edge server or

the origin server and the requested application. The URI for the proxy cluster or the origin

server is not found on the client. Reverse proxying requires a different strategy for connecting

clients and applications.

Clustering works efficiently when all clients that request the same application instance

connect to the same edge server in the cluster, where the application is cached. To accomplish

this efficiency with reverse proxying requires a multistep procedure.

1. The client sends an HTTP request that includes an XML.load call to the origin server:

http://origin[:<port>]/fms/fpad?uri=<uri>

The load balancer on the remote network intercepts the request and routes it to one of the

edge servers in the cluster.

3. This edge server then acts as an FPAD client and broadcasts an FPAD message.

4. The edge servers enrolled in the cluster respond with their affinity values.

5. The broadcasting edge server chooses the edge server with the lowest affinity value.

6. This edge server sends the required information back to the client:

<?xml version=\"1.0\" encoding=\"utf-8\" ?>

<fpad>

</fpad>

where the <proxy> tag contains the host:ip address of the edge server to connect to.

18 Using Edge and Origin Servers

7. The client then uses the information to make an explicit connection: first to the edge, then

to the origin server using a wrapped URI:

nc = new NetConnection();

nc.onStatus = function(info)

{

trace(info.code);

}

uri = "rtmp://yourcompany.com/app/inst";

myXML = new XML();

myXML.onLoad = function(success)

{

if (success)

{

var proxy = this.childNodes[1].childNodes[1].firstChild.nodeValue;

uri = "rtmp://" + proxy + "/?" + uri;

}

nc.connect(uri);

}

myXML.load("http://yourcompany.com/fcs/fpad?uri=" + uri);

The /fcs/fpad? code in the XML.load() URI tells the edge server that it needs to broadcast

an FPAD message using the URI named

uri, as specified.

Setting up origin and proxy servers

Use the following guidelines as you install and configure the origin and proxy servers. Using

these guidelines helps ensure satisfactory performance and results:

■ Make sure your Macromedia license permits you to use proxy servers or a proxy cluster.

■ Deploy all proxy and origin servers on identical computers.

■ Use the same operating system (Linux or Windows) on all computers to avoid conflicts

with filenames.

Linux uses case-sensitive filenames; filenames on Windows are case-insensitive.

■ Install Flash Media Server on the first server.

■ Configure this instance of Flash Media Server as an origin server.

■ Install and configure Flash Media Server on all of the edge or proxy servers that your

license permits.

■ Make sure the fms.ini file is customized on each origin and proxy.

The fms.ini file is machine-specific.

■ Configure the origin server to listen on one port; you can configure proxies to listen on

one or multiple ports.

■ Verify that all proxies can access the origin server.

Introducing edge servers 19

■ Locate the origin server and those edge servers nearest to it on the same subnet.

■ If you are licensed to deploy a cluster, make sure all proxies in the cluster are configured

identically.

■ Configure the conf directory on one proxy.

■ Place a copy of this conf directory in the same location on the other proxies.

■ Use a load balancer when you deploy more than one proxy.

■ Place the load balancer between the clients and the proxies.

■ Configure the balancer to access the proxies in round-robin mode.

■ Do not place the load balancer immediately before the origin server.

To set up a cluster of edge servers:

1. Install and configure the first Flash Media Server.

Use the same serial number and license file each time you install Flash Media Server.

2. Confirm that this Flash Media Server instance is working correctly.

3. Configure the Flash Media Server instance as an origin server.

4. Install and configure the next Flash Media Server in the cluster.

5. Configure this Flash Media Server instance as an edge server.

6. Make sure this edge server points to the origin server.

7. Repeat steps 5 through 7 for each edge server that your license file allows.

Your Flash Media Servers are now clustered. To expand the cluster’s capacity, you may add

new edge servers, if your license permits, to the cluster and configure them by following these

instructions.

Maintaining edge server clusters

When an edge starts up, it broadcasts its presence to all other edges in the cluster. When an

edge shuts down, it broadcasts that it is leaving the cluster. If an edge shuts down, all other

edges in the cluster detect the change in state because the edges no longer receive the keep-

alive messages from that edge. The remaining edges automatically update their views of the

cluster and remove the shut-down edge from their views. You only have to start and stop

edges, and they automatically determine which edges are currently enrolled in the cluster.

NOTE

A special cluster license file is required. For more information, contact your

Macromedia representative.

20 Using Edge and Origin Servers

Clearing the edge server cache

Macromedia recommends that you create a weekly scheduled task to clear the edge server

cache.

To create a scheduled cache clearance:

1. Create a cache.bat file to empty the cache directory.

The entry in the cache.bat file has the following syntax:

del /Q /S <cache_directory>\*.*

Run the cache.bat file and verify that it deletes files in the cache directory.

■ Note that the directory structure remains; this is an expected behavior.

■ Any files currently locked by the edge server are not deleted; this is also an expected

behavior.

3. Select Control Panel > Scheduled Tasks > Add Scheduled Task.

4. Select cache.bat as the new file to run.

Macromedia recommends that you schedule the task to run weekly during off hours, such

as early Sunday morning.

Replicate this procedure on each edge server.

MACROMEDIA FLASH MEDIA SERVER 2-USING FLASH MEDIA SERVER EDGE SERVERS Use Manual

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