User`s manual

Installing under UNIX/LINUX
78 AX3000 - User's Manual
Main characteristics of a tty session:
- Pre-defined allocation of pseudo-terminals (ptty),
- UNIX access is controlled by a 'login', which is generated by the init
daemon (controlled by the /etc/inittab file).
The Unix/Linux host must run the AXEL tty server daemon (axttyd). The
configuration file axttyd must contain a list of AX3000 sessions and the pttys
associated with each.
Each session is identified by the name of the AX3000 (from the /etc/hosts file)
and a special keyword (sessx where x is the session number). For example:
axel1 sess1 /dev/ptyp12 /dev/ttyp12
axel1 sess2 /dev/ptyp13 /dev/ttyp13
axel2 sess2 /dev/ptyp2 /dev/ttyp2
A terminal session controlled by the tty server acts as a serial terminal attached
to a multi I/O board. The /etc/inittab file must therefore be modified to launch
the getty command for each pseudo-terminal.
Example for SCO Unix: get a login on /dev/ttyp12:
p12:23:enable:/etc/getty -t60 /dev/ttyp2 m
This modification will take effect after invoking the following command:
# init q <CR>
For more information about the Axel tty server, refer to Chapter 5.4.
c) The SSH Protocol
An SSH connection can be considered as an encrypted telnet connection. Main
characteristics are:
- Dynamic allocation of pseudo-terminals (ptty),
- System access is controlled by a 'login', which is generated by the sshd
daemon (available with most versions of Unix/Linux),
- The value of the TERM environment variable is negotiated after the login
stage. (See Chapter 5.1.7 for default TERM values.)