Lantronix ETS Reference Manual - 7.3 Reverse Telnet (Rtel)
Reverse Telnet (RTEL)
TCP/IP Host Setup
7-10
Note:
Due to problems in the Solaris queueing system, LPR is not reliable on Solaris
machines. Users with Solaris hosts should use the RTEL software provided by
Lantronix.
7.3 Reverse Telnet (RTEL)
If LPR is not adequate for an application (for example, if banners are needed before jobs or more flexibility
is needed in printing), the supplied RTEL software can be configured on the host.
RTEL is a set of programs designed to allow host-initiated connections to devices attached to your terminal/
print server. The RTEL software is simply a transport mechanism, and as such, it makes no assumptions
about the actual devices attached to the server. Once the software is installed and connections to the ETS
have been configured, normal UNIX print commands and queue utilities (such as lpc and lpstat) can be used.
The RTEL software is supported on seven platforms: AIX on IBM RS6000’s, HP/UX on HP platforms,
RISC/OS on MIPS workstations, SCO on PC platforms, IRIX on SGI machines, Solaris on SUN
workstations, and SUN/OS on SUN workstations. If the target machine is not one of these platforms, some
modification may be necessary to make the RTEL software compile, link, and run properly. See the RTEL-
build man page for hints on building on unsupported platforms.
Note:
RTEL Binaries are provided for many systems and source code is provided for
use on non-supported systems. See the Lantronix web site at http://
www.lantronix.com.
7.3.1 Components of RTEL
RTEL provides two main types of interfaces to the server. The first is a printer backend filter for BSD,
SYSV, and AIX type printing subsystems. The second method of printing with RTEL uses a UNIX named
pipe as the actual interface to the host system.
The backend filter simply accepts data from the queue manager (LPD for BSD, lpsched for SYSV, and
qdaemon on AIX) and moves that data over the network to the terminal/print server. The backend filter can
perform simple reformatting of the job, such as tab expansion,
pages. It cannot, however, perform complicated tasks such as PostScript conversion. See the RTEL-
backend man page for more information.
The named pipe interface allows host-supplied or third party software to send output to a device (the pipe)
after which the RTELPD daemon process sends the data to the server. See the RTELPD man page for more
information.
7.3.2 Installing Reverse Telnet Software
RTEL software is provided on the distribution CD-ROM in tar format and can be restored into a local
directory. To set up the RTEL Software,
1
Install the RTEL software.