This chapter describes the function and configuration of the Terminal Server. In conjunction with the HELIOS Terminal application, the Terminal Server allows workstations in the AppleTalk network to make simultaneous terminal connections to one or more UNIX hosts (multiple sessions capability).
15.2 The Terminal Server Program
The EtherShare Terminal Server system consists of the program "termsrv". It is created automatically in the "$ESDIR" directory during installation. EtherShare is configured to start "termsrv" automatically when UNIX is booted.
"termsrv" implements terminal server functions on the host and manages the communication with HELIOS Terminal. Each new login request from a Macintosh workstation starts a new host login process. "termsrv" then re-directs the host's input and output to the workstation via the network.
15.3 Parameters of "termsrv" program
When it starts, the Terminal Server program "termsrv" first accesses the main configuration file "atalk.conf" to determine its configuration. The "install" program automatically sets up this file with initial values. The values can be changed if necessary by using an editor such as vi. See also chapter
5.14 "Editing "atalk.conf" (and other configuration files) manually".
The parameters described below can be defined for "termsrv" in "atalk.conf" (note that the parameter list is preceded by the program name "termsrv"):
name=netname,name=netname2,name=netname3
netname is the AppleTalk (NVE) name of the Terminal Server. This is the name with which it is known to the network. It is the name you see in the
Chooser of the HELIOS Terminal program. Several names in a row, separated by a comma, are optional.
The default for
netname is the name of the UNIX host.
nettype is the AppleTalk type of the Terminal Server. This is the type with which it is known to the network.
nettype should normally be set to "UNIXTerminal". The same type must be set in the "Connection Settings" window of the HELIOS Terminal program.
The default for
nettype is "UNIXTerminal".
zone=zonename,zone=zonename2,zone=zonename3
zonename is the name of the AppleTalk zone to which the Terminal Server should be allocated. This parameter determines the zone in which the Terminal Server can be seen in the Chooser of the HELIOS Terminal program. The chosen zone must be one of the local zones that the host is connected to. You can test this with the "zones -l" program (see
zone in chapter
13.3 "Parameters of the "admsrv" program").
The default for
zonename is "*", i.e. the zone of the first interface entry in "atalk.conf". Several names in a row, separated by a comma, are optional, e.g.:
termsrv: zone="marketing", zone="support",
zone="developer"
maxlpackets specifies the maximum number of data packets that are passed from "termsrv" to workstations through the network during a transaction. The number of packets may need to be limited if the buffer size in the workstations is too small.
maxlpackets can be varied to optimize the data transfer rate.
The default (and maximum) for
maxlpackets is 8.
remotewinsize=maxrpackets
maxrpackets specifies the maximum number of data packets that are passed from workstations to "termsrv" through the network during a transaction. The number of packets may need to be limited if the buffer size in the UNIX host is too small.
maxrpackets can be varied to optimize the data transfer rate.
The default (and maximum) for
maxrpackets is 8.
capname is the name of the terminal emulation. This name is written by "termsrv" to the UNIX environment variable "$TERM" on starting a new connection. In the standard UNIX configuration, the VT100 emulation (i.e. a definition of terminal control codes) is defined in each of the files "termcap" and "terminfo". If you change
capname to specify another emulation, you must ensure that the new emulation definition has been added to both files. Whereas many programs refer to the "termcap" file, an entry is also required in "terminfo", since, under Solaris 2, some programs refer to "terminfo" (like the editor program vi) instead of "termcap". Note that the standard UNIX VT100 emulation is a subset of the VT320 emulation provided in HELIOS Terminal.
The default for
capname is
vt100.
bannerstring is a string which is output to each Macintosh terminal whenever a connection is made and before the login itself is started. For example, you can use this parameter to output a company trademark. The following escape sequences are recognized within
bannerstring:
%n The host name of the UNIX system
\r A Carriage Return character
\033 An Escape character. This allows any
required bit pattern to be constructed
with a 3-position octal number.
If you do not specify
bannerstring, the default is:
"\r\n\r\nADSP Terminal Server on host
%n\r\n\r\n(C) 1990 Helios Software GmbH\r\n\r\n".
Specify
banner="" if you do not want a banner.
