The services file (SystemFolder\drivers\etc\services) on the Operations Sentinel server describes port numbers and protocols. For each port you want to use, you must specify its port number and protocol in this services file. You must log on as the administrator to update this file. The format of each line in the services file is as follows:

service-name  port/protocol   
communications-parameters   # comment

where:

service-name

is an arbitrary name. Every assigned port descriptor must have a unique service name.

port

is the descriptor (a number or a name) of a port on a terminal/communications server, or the name of the COM port used on the Operations Sentinel server.

protocol

the name for the external alert application. eai_ats is the protocol name for terminal/communication server connections (including ATS and NAS connections) for modems and serial devices. This protocol identifies an ATS port number. eai_serial is the protocol name for connections using the COM port on the Operations Sentinel server.

communications-parameters

can be used to change the port offset location when protocol eai_ats is specified. Enter the values in uppercase letters with no spaces. If you misspell or use an unrecognizable value, the system ignores it. Where more than one value is applicable, you can specify them in any order separated by a space or tab.

Specify Port offset location as OFFSETnumber; where number is the value needed to make a connection with the terminal/communications server raw data interface. The default is OFFSET7000.

comment

is any optional descriptive information about this entry. It must follow a pound character (#).

When sending alert actions through a terminal/communications server, Operations Sentinel uses a special raw data interface from the Operations Sentinel server to the terminal/communications server. This interface behaves similarly to the managing interface, but does not utilize TELNET protocol. On an ATS or NAS, this connection is made by Operations Sentinel offsetting the physical port number by 7000. On Cisco servers, this is initiated by using an offset of 4000. If you are using a terminal/communications server other than an ATS, NAS, or Cisco 2500 Series Access Server for alert actions, you must ensure that it provides a similar connection interface and configure it similarly to the method described for the Cisco server in Appendix H.9.1, “Configuring a Port on a Cisco 2500 Series Access Server.”