Services Explained
- Jane
Please explain how services work on your print and terminal servers.
Overview
Services are mostly used for printing so Lantronix Print, Terminal and Remote Access servers will be referred to as Printservers for the rest of this FAQ.
A service is a resource accessible to network hosts; for example, an AppleTalk user may queue print jobs to a service. Services control which protocols can use the printserver ports and how these ports appear to network users. In general, there has to be at least 1 service associated with a port before that port can be available to network users.
ETS SCSx00 and LRS products
There are no default services on ETS terminal servers or SCSx00 Secure Console Servers. You can create a service and associate it with a port with the privileged command SET/DEFINE SERVICE servicename PORTS n-m where n-m is a range of port numbers. For instance to create a new service named FRED on port 5 of an ETS or SCSx00:
- type SET PRIV to become the privileged user (the default priv Pass-word is SYSTEM).
- type:
SET SERVICE FRED PORT 5
DEFINE SERVICE FRED PORT 5
to create a service named FRED for port 5. See "Characteristics" below to find out how to modify a service’s characteristics.
EPS Products
Lantronix EPS Printservers offer a default service on each port. The service names are EPS_xxxxxx_yy where xxxxxx represents the last six numbers of the unit's Ethernet address and yy is the port name, for example S1 or P1.
The default services on the serial ports of EPSs have the LAN Manager, NetWare, and TCP/IP protocols enabled. LAT is disabled by default on services provided by the EPS because many network managers object to the frequent LAT service announcements. See the Characteristics section below for an explanation of other configurable service characteristics.
MPS and LPS Products
On MPS and LPS printservers the default service names start with MPS or LPS. MPSs and LPSs have 3 default services ending in _TEXT, _PCL and _PS for text data, binary data and Postscript data respectively. So for instance an MPS1 will have 3 default services named MPS_xxxxxx_TEXT, MPS_xxxxxx_PCL and MPS_xxxxxx_PS, where xxxxxx represents the last six numbers of the unit's Ethernet address.
Note: The default service names are based on the server name; therefore the server name must be 13 characters or less.
MPS1 and LPS1 default services are not configurable. If you need different attributes than the ones already set on the default services you'll need to create a custom service. See the section on creating services on Terminal Servers above.
Creating and Modifying Services
To modify a default service on an EPS or a custom service on ETSs, MPSs and LPSs, use the SET/DEFINE SERVICE command with any of the attributes, characteristics, and protocols discussed in the following sections.
If you modify the service name, keep in mind that service names are not case-sensitive, may be up to 16 alphanumeric characters long, and cannot include spaces.
Note: Each service must be associated with at least 1 port. To associate a port with a service, use the SET/DEFINE SERVICE PORTS command. If different service characteristics are necessary for printing from different types of host machines, multiple services all pointing to the same physical port can be created. The services can have their own unique characteristics.
Attributes
Service Name
Each service has a name. The name is assigned when the service is first created. Services can't be renamed. If you want to change the name of a service you'll need to create a new service with the same characteristics, then PURGE the old service.
EOJ (End-of-Job) or SOJ (Start-of-Job) String
Each service may have an End-of-Job or Start-of-Job string (or both). EOJ strings will be sent to the printer after every print job; SOJ strings will be sent to the printer before each print job. These strings are typically used to force the printer into a particular mode (such as PostScript or PCL). When specifying a string, use the following syntax:
Examples of EOJ and SOJ Strings:
Local>> DEFINE SERVICE EPS_PRT SOJ "startchar"
Local>> DEFINE SERVICE EPS_PRT EOJ "\23\4e\9atext"
Note: The commands that you may want or need to enter in EOJ and SOJ strings are printer-specific; therefore they are not covered in this FAQ.
Note: If you are using PostScript printing on an auto-sensing printer, you may not need to enter EOJ or SOJ strings to force the printer into PostScript mode; enabling the PostScript characteristic (see PostScript) should do this. For more details, refer to your printer's documentation.
Ident String
Each service may have an identification string. This string typically contains a more verbose description of the service and is displayed by LAT when a Show Services command is issued. However, it is ignored by all other protocols.
Rating
The rating describes the current state of the service. A non-zero value means the service is available. Zero means that the service is either in use or not available. The rating is not configurable, it's assigned by the printserver's operating system depending on the status of the service.
Ports
The port list shows which port(s) the service is associated with. A port is associated with a service with the command SET/DEFINE SERVICE servicename PORTS n-m, where n-m is a range of port numbers.
Characteristics
These options specify how the printserver appears to network hosts and
how it treats print data.
Service Characteristics can be enabled or disabled with the SET/DEFINE
SERVICE servicename characteristic_name ENABLED/DISABLED command.
Banner
This parameter only affects printserver banner pages when printing via LPD or NetWare. If a host generates its own banner, the printserver treats it as print data. By default, the printserver adds a banner page to LPD and NetWare jobs.
Binary
If the binary option is specified, the printserver will not perform character processing on the data. By default (binary disabled) the printserver expands linefeeds into carriage return/linefeeds and performs tab expansion for LPD jobs. The binary option should be enabled for printing graphics jobs.
PostScript
If enabled, the printserver sends a small PostScript job to the printer before the print data to force auto-selection printers into PostScript mode. It also attempts to confirm that the printer finished a job before starting the next one. If the printer attached to this service will be used only for PostScript, this option must be enabled.
PSConvert
This characteristic allows a PostScript printer attached to the printserver to print non-PostScript jobs. When a file is queued to a service with the PSConvert attribute enabled, the file is encapsulated within a PostScript job. PSConvert is disabled by default.
TCP Port
The TCP Port characteristic associates a numeric TCP socket (between 4000 and 4999) with the service. Connections to this socket will be accepted only if the service is currently available. This is an 8-bit clean connection.
Telnet Port
The Telnet Port characteristic associates a numeric TCP socket (between 4000 and 4999) with the service. Telnet IAC interpretation will be done on the connection. Connections to this socket will be accepted only if the service is currently available.
Protocols
Each service has a protocol list associated with it; this list controls which protocols can access the service. Protocol parameters include AppleTalk, LAN Manager, LAT, NetWare, and RTEL (TCP/IP). To enable all protocols on a service use multiple SET/DEFINE SERVICE servicename PROTOCOL protocolname ENABLED commands.
Displaying Current Services
To examine a service's attributes and characteristics, issue the SHOW SERVICE command. Here's an example from an EPS:
Local> SHOW SERVICE EPS_xxxxxx_yy CHARACTERISTICS
Service: EPS_xxxxxx_yy Ident: EPS Serial Port
Rating: 255 Ports: 1
Characteristics: Queuing Rtel Connections Appletalk Netware
Enabled Groups: 0
SOJ: startchar EOJ: endchar
[Originally Published On: 07/12/1999 12:37 PM]