Preparing the Load Balancer and Firewalls for an Enterprise Deployment

6 Preparing the Load Balancer and Firewalls for an Enterprise Deployment

It is important to understand how to configure the hardware load balancer and ports that must be opened on the firewalls for an enterprise deployment.

Configuring Virtual Hosts on the Hardware Load Balancer

The hardware load balancer configuration facilitates to recognize and route requests to several virtual servers and associated ports for different types of network traffic and monitoring.

The following topics explain how to configure the hardware load balancer, provide a summary of the virtual servers that are required, and provide additional instructions for these virtual servers:

Overview of the Hardware Load Balancer Configuration

As shown in the topology diagrams, you must configure the hardware load balancer to recognize and route requests to several virtual servers and associated ports for different types of network traffic and monitoring.

In the context of a load-balancing device, a virtual server is a construct that allows multiple physical servers to appear as one for load-balancing purposes. It is typically represented by an IP address and a service, and it is used to distribute incoming client requests to the servers in the server pool.

The virtual servers should be configured to direct traffic to the appropriate host computers and ports for the various services that are available in the enterprise deployment.

In addition, you should configure the load balancer to monitor the host computers and ports for availability so that the traffic to a particular server is stopped as soon as possible when a service is down. This ensures that incoming traffic on a given virtual host is not directed to an unavailable service in the other tiers. At the same time, this monitoring should not overload the back-end system with too frequent health requests. In the end, a trade off needs to be made between how fast the death detection occurs and how much overhead is introduced on the systems that are monitored.

Note that after you configure the load balancer, you can later configure the web server instances in the web tier to recognize a set of virtual hosts that use the same names as the virtual servers that you defined for the load balancer. For each request coming from the hardware load balancer, the web server can then route the request appropriately, based on the server name included in the header of the request. See Configuring Oracle HTTP Server for Administration and Oracle Web Services Manager.

Typical Procedure for Configuring the Hardware Load Balancer

The following procedure outlines the typical steps for configuring a hardware load balancer for an enterprise deployment.

Note that the actual procedures for configuring a specific load balancer will differ, depending on the specific type of load balancer. There may also be some differences depending on the type of protocol that is being load balanced. For example, TCP virtual servers and HTTP virtual servers use different types of monitors for their pools. Refer to the vendor-supplied documentation for actual steps.

Create a pool of servers. This pool contains a list of servers and the ports that are included in the load-balancing definition.

For load balancing between the web hosts, create a pool of servers that would direct requests to hosts WEBHOST1 and WEBHOST2 to each port used in the OHS. For example, a pool to WEBHOST1 and WEBHOST2 to port 4443 for access to applications like WebCenter Content, another pool to WEBHOST1 and WEBHOST2 to port 4444 for internal accesses, and another pool to WEBHOST1 and WEBHOST2 to port 4445 for access to administration consoles.
Create rules to determine whether a given host and service is available and assign it to the pool of servers that are described in Step 1.
Create the required virtual servers on the load balancer for the addresses and ports that receive requests for the applications.

For a complete list of the virtual servers required for the enterprise deployment, see Summary of the Virtual Servers Required for an Enterprise Deployment.

When you define each virtual server on the load balancer, consider the following:
1. If your load balancer supports it, specify whether the virtual server is available internally, externally, or both. Ensure that internal addresses are only resolvable from inside the network.
2. Assign the pool of servers created in Step 1 to the virtual server.
3. Configure SSL for the virtual server.
4. Configure SSL for the communication with the pool of servers.

Some load balancers may need to be provided with the back end's certificate (the SSL certificate used by the OHS listeners in the back-end pool) to establish the appropriate SSL communication. In that case, you may need to add the OHS's CA certificate to the load balancer as a trusted certificate. Because this guide uses example certificates based on the WebLogic per-domain CA, you can add this after the domain is created.

Summary of the Virtual Servers Required for an Enterprise Deployment

This topic provides details of the virtual servers that are required for an enterprise deployment.

The following table provides a list of the virtual servers that you must define on the hardware load balancer for the Oracle WebCenter Content enterprise topology:

Virtual Host Server Pool Protocol SSL Termination?

Virtual Host	Server Pool	Protocol	SSL Termination?
`admin.example.com:445`	`WEBHOST1.example.com:4445` `WEBHOST2.example.com:4445`	HTTPS	No
`wcc.example.com:443`	`WEBHOST1.example.com:4443` `WEBHOST2.example.com:4443`	HTTPS	No
`wccinternal.example.com:444`	`WEBHOST1.example.com:4444` `WEBHOST2.example.com:4444`	HTTPS	No

admin.example.com:445

WEBHOST1.example.com:4445

WEBHOST2.example.com:4445

HTTPS

wcc.example.com:443

WEBHOST1.example.com:4443

WEBHOST2.example.com:4443

HTTPS

wccinternal.example.com:444

WEBHOST1.example.com:4444

WEBHOST2.example.com:4444

HTTPS

Additional Instructions for admin.example.com

This section provides additional instructions that are required for the virtual server-admin.example.com.

When you configure this virtual server on the hardware load balancer:

Enable address and port translation.
Enable reset of connections when services or hosts are down.

Additional Instructions for wcc.example.com

The address wcc.example.com is a virtual server name that acts as the access point for all HTTP traffic to the runtime Oracle WebCenter Content components. Traffic to SSL is configured. Clients access this service using the address wcc.example.com:443 for HTTP. When you configure this virtual server on the hardware load balancer:

Use port 443. If port 80 is used for customer usability, then it is recommended to redirect any requests to it (non-SSL protocol) to port 443 (SSL protocol). Refer to your load balancer’s specific documentation to implement this redirection.
Specify ANY as the protocol (non-HTTP protocols are required for B2B).
Enable address and port translation.
Enable reset of connections when services and/or nodes are down.
Create rules to filter out access to /management and /em on this virtual server.

These context strings direct requests to Oracle WebLogic Remote Console and to Oracle Enterprise Manager Fusion Middleware Control and should be used only when accessing the system from admin.example.com.

Additional Instructions for wccinternal.example.com

The address wccinternal.example.com is a virtual server name used for internal invocations of WebCenter Content and SOA services. This URL is not exposed to the Internet and is accessible only from the intranet. The incoming traffic from clients is not SSL enabled.

When you configure this virtual server on the hardware load balancer:

Enable address and port translation.
Enable reset of connections when services or nodes are down.
As with wcc.example.com, create rules to filter out access to /management and /em on this virtual server.

Configuring the Firewalls and Ports for an Enterprise Deployment

As an administrator, it is important that you become familiar with the port numbers used by various Oracle Fusion Middleware products and services. This ensures that the same port number is not used by two services on the same host, and that the proper ports are open on the firewalls in the enterprise topology.

The following tables lists the ports that you must open on the firewalls in the topology:

Firewall notation:

FW0 refers to the outermost firewall.
FW1 refers to the firewall between the web tier and the application tier.
FW2 refers to the firewall between the application tier and the data tier.

Table 6-1 Firewall Ports Common to All Fusion Middleware Enterprise Deployments

Type	Firewall	Port and Port Range	Protocol / Application	Inbound / Outbound	Other Considerations and Timeout Guidelines
Browser request	FW0	80 Note: You need this option only if redirection from port 80 to port 443 is used.	HTTP / Load Balancer	Inbound	Timeout depends on the size and type of HTML content.
Browser request	FW0	443	HTTPS / Load Balancer	Inbound	Timeout depends on the size and type of HTML content.
Browser request	FW1	80 Note: You need this option only if redirection from port 80 to port 443 is used.	HTTPS / Load Balancer	Outbound (for intranet clients)	Timeout depends on the size and type of HTML content.
Browser request	FW1	443	HTTPS / Load Balancer	Outbound (for intranet clients)	Timeout depends on the size and type of HTML content.
Callbacks and Outbound invocations	FW1	80	HTTPS / Load Balancer	Outbound	Timeout depends on the size and type of HTML content.
Callbacks and Outbound invocations	FW1	443	HTTPS / Load Balancer	Outbound	Timeout depends on the size and type of HTML content.
Load balancer to Oracle HTTP Server	n/a	444x	HTTPS	n/a	n/a
Session replication within a WebLogic Server cluster	n/a	n/a	n/a	n/a	By default, this communication uses the same port as the server's listen address.
Database access	FW2	1521	SQL*Net	Both	Timeout depends on database content and on the type of process model used for WebCenter Content.
Coherence for deployment	n/a	9991 Coherence requires the following connectivity between members: Port 9991 for both UDP and TCP for both multicast and unicast configurations. TCP port 7. Ephemereal ports 32768-60999 for both udp and tcp.		n/a	n/a
Oracle Unified Directory access	FW2	389 636 (SSL)	LDAP or LDAP/ssl	Inbound	You should tune the directory server's parameters based on load balancer, and not the other way around.
Oracle Notification Server (ONS)	FW2	6200	ONS	Both	Required for Gridlink. An ONS server runs on each database server.

Table 6-2 Firewall Ports for Product-specific Components in Oracle Fusion Middleware Enterprise Deployments

Type	Firewall	Port and Port Range	Protocol / Application	Inbound / Outbound	Other Considerations and Timeout Guidelines
Oracle SOA Suite and WSM Server access	FW1	8001 Range: 8000 - 8080	HTTPS / WLS_SOAn	Inbound	Timeout varies based on the type of process model used for SOA.
Oracle WebCenter Content Access	FW1	16201	HTTPS / WLS_WCCn	Inbound	Browser-based access. Configurable session timeouts.
Oracle WebCenter Enterprise Capture access	FW1	16401	HTTPS / WLS_CPTn	Inbound	Browser-based access. Configurable session timeouts.
Communication between SOA_Cluster members	n/a	8001	TCP/IP Unicast	n/a	By default, this communication uses the same port as the server's listen address.
Communication between WCC_Cluster members	n/a	16201	TCP/IP Unicast	n/a	By default, this communication uses the same port as the server's listen address.
Communication between CPT_Cluster members	n/a	16401	TCP/IP Unicast	n/a	By default, this communication uses the same port as the server's listen address.