Parameter

Description

Unit

Default Value

icm/server_port_<xx>

Starting point for requests, protocols, timeouts, etc.

You have to define this parameter.

Character string

-

wdisp/auto_refresh

The period of time after which the route information tables of the SAP Web dispatcher (server tables, group tables and URL mapping tables) are periodically updated.

Seconds

120

wdisp/max_servers

This parameter determines the maximum number of entries in the SAP Web dispatcher’s server table.                          

Whole number (between 64 and 4096)

128

wdisp/max_server_name_len

This parameter specifies the maximum length of an entry in the SAP Web dispatcher’s server table, that is, the maximum length of an instance name (profile parameter rdisp/myname of the individual servers).

Whole number (between 32 and 128)

64

wdisp/max_server_groups

This parameter determines the maximum number of entries in the SAP Web dispatcher’s group table.

Whole number (between 32 and 4096)

128

wdisp/max_server_group_name_len

This parameter determines the maximum length of an entry in the SAP Web dispatcher’s group table.

You maintain logon groups in transaction SMLG.     

Whole number (between 20 and 64)

20

wdisp/max_url_map_entries

This parameter determines the maximum number of entries in the SAP Web dispatcher’s URL mapping table.       

Whole number (between 100 and 10000)

300

wdisp/max_url_map_path_len

This parameter determines the maximum path length in the SAP Web dispatcher’s URL mapping table.                                

Whole number (between 100 and 2048)

256

wdisp/server_info_location

Specifies from where the SAP Web dispatcher obtains information about the SAP Web Application Server, to which it can distribute the Web requests.

The SAP Web Dispatcher gets its information from the Message Server. The parameter indicates the (relative) URL where in the Message Server this information is.

Character string

/msgserver/

text/logon

wdisp/group_info_location

Specifies from where the SAP Web dispatcher obtains information about the server groups, to which it can distribute the Web requests.

The details are indicated in a URL (absolute or relative).

Usually the SAP Web Dispatcher gets its group information from an application server (transaction SMLG). In this case you can specify the ICF service, where the groups are defined.

If there is no application server with ICF (ABAP) available, you can store this information in a file. In this case you can use this parameter to specify the file path by setting the parameter to file://<path>.

Character string

/sap/public/

icf_info/

icr_groups

wdisp/url_map_location

URL under which the SAP Web Dispatcher finds the URL mapping info.

This is usually a path in the HTTP service hierarchy of the application server (transaction SICF).

If there is no application server with ICF (ABAP) available, you can store this information in a file. In this case you can use this parameter to specify the file path by setting the parameter to file://<path>.

URL path name

/sap/public/

icf_info/icr_

urlprefix

wdisp/server_info_protocol

wdisp/group_info_protocol

wdisp/url_map_protocol

Protocol that the SAP Web Dispatcher should use for communicating with the message server and the application servers for exchanging metadata (server list, logon groups, URL mapping).

With HTTPS you can make this communication secure, see Metadata Exchange Using SSL.

Protocol name, possible values: HTTP or HTTPS

HTTP

wdisp/permission_table

Absolute or relative path for URI permission table. Further profile parameters for configuring the URI permission table are described in section SAP Web Dispatcher as URL Filter.

Character string (file path)

Wdisp/HTTPS/dest_logon_group

See SSL Parameters

wdisp/HTTPS/sticky_mask

wdisp/HTTPS/

max_client_ip_entries

wdisp/HTTPS/context_timeout

wdisp/HTTP/max_pooled_con 

This parameter determines the maximum number of HTTP connections in the connection pool from the SAP Web dispatcher to an SAP Web Application Server.                                                            

You do not normally need to change the default setting.  

Number of connections

32768

wdisp/HTTP/min_pooled_con

Minimum number of HTTP connections that are kept in the SAP Web dispatcher’s connection pool for each application server. This number of connections is kept before the first HTTP request is received.                                       

Number of connections

2

wdisp/HTTPS/max_pooled_con

See SSL Parameters

wdisp/HTTPS/min_pooled_con

wdisp/ssl_encrypt

wdisp/ssl_auth

wdisp/ssl_cred   

wdisp/ssl_certhost

wdisp/load_balancing_strategy

Load balancing strategy of the SAP Web dispatcher, see Server Selection and Load Balancing Using the SAP Web Dispatcher

Load balancing strategy

Possible values:

weighted_round_robin

simple_weighted_round_robin

adaptive

weighted_round_robin

wdisp/add_xforwardedfor_header

The parameter determines whether the SAP Web dispatcher includes the IP address of the client in the header field x-forwarded-for. If it does, the application on the application server can read the route that the request has taken. If the parameter has the value false, the Web dispatcher leaves the header field unchanged.

Truth variable (true or false)

false

wdisp/add_client_protocol_header

This parameter determines whether the protocol between the browser and the Web dispatcher (HTTP or HTTPS) is notified to the application server.

This information is sent in the header field clientprotocol.

If there is a change in protocol in the Web dispatcher, the application server requires this information, to generate absolute URLs (it can get the Web dispatcher host and port names from the header field Host).

Truth variable (true or false)

false

wdisp/handle_webdisp_ap_header

With this parameter the Web dispatcher notifies the application server of its ports (access points) for the different protocols in an HTTP header. In the application server the protocol can be switched without any manual configuration (for example, from HTTP to HTTPS), or a redirect can be programmed.

The header field set by the Web dispatcher has the syntax:

x-sap-webdisp-ap: http=<port>, https=<port>, <protocolXYZ>=<port>

For example:

x-sap-webdisp-ap: http=80,https=443

x-sap-webdisp-ap: http=80

Integer between 0 and 3; the values mean the following:

0: No action (old behavior)

1: Header field with it own access information (if this field exists, it is set)

2: Set header field if not already set.

3: Delete header field. if it exists.

0

wdisp/enable_sap_hostid

If the value of this parameter is true, a server destination can be specified explicitly in the request URI using the form field sap-hostid, to directly override the load balancing.

This is needed, for example, for debugging server nodes or for test purposes.

webdisp.wdf.sap.corp:4711/sap/public/icman/ping?sap-hostid=binmain_BIN_53

Since with this form field server load balancing can be bypassed (denial of service attacks), the default is this behavior is deactivated and must be explicitly activated using the parameter above.

Truth variable (true or false)

false

wdisp/redispatch_foreign_sessions

If the value of this parameter is true, the Web dispatcher tries to find an alternative server using stateless load balancing for failed stateful requests (incorrect session cookie in target server cannot be accessed).

This has the following advantages:

The relevant backend (J2EE, ABAP) returns more meaningful error pages (such as "Please log on again"). The Web dispatcher remains transparent for the user.

A real session failover is made possible, if the relevant server backend is in the position to transfer external sessions

For security reasons this feature must also be explicitly activated in the above profile parameter.

Truth variable (true or false)

false

wdisp/HTTP/esid_support

wdisp/HTTP/jsessionid_tab_support

wdisp/HTTP/max_session_tab_logon_groups

wdisp/HTTP/max_session_tab_entries

wdisp/HTTP/context_timeout

The parameters below are used to configure the session dispatching. They are described in Parameter Settings for Session Dispatching.