16
4.2 Serial Tunnel Example
Two Terminal Servers can be connected to emulate a direct serial connection across a LAN
or WAN. Servers connected in this way can pass data only—they will not be able to pass
status signals (DSR/DTR, CTS/RTS, etc.) or preserve timing between characters. The basic
network configuration for this virtual serial line is shown in Figure 4-15.
Figure 4-15:
Back-to-Back Terminal Server Connections
4.2.1 TCP Configuration
Assuming the Terminal Server serial port parameters have been configured properly, the
Terminal Servers would be configured as follows.
LES_A
Local>> DEFINE PORT 2 DEDICATED TELNET 192.168.5.10:3001T
Local>> DEFINE PORT 2 AUTOSTART ENABLED
LES_B
Local>> DEFINE PORT 3 ACCESS REMOTE
Local>> DEFINE PORT 3 DEDICATED NONE
Local>> DEFINE PORT 3 AUTOSTART DISABLED
Note:
If the Terminal Servers are on different IP subnets, configure the de-
fault gateway on each unit with the Change Gateway command.
The above commands create a raw (8-bit clean) TCP connection between
LES_A
port 2
and
LES_B
port 3 once the units have been power-cycled. The commands for
LES_A
ensure that it will automatically connect to
LES_B
each time it is booted. The commands
for
LES_B
ensure that it is always available to accept connections from
LES_A
.
Note:
You must log out the Terminal Server ports after configuring them so
that the commands can take effect.
4.2.2 UDP Configuration
When the UDP protocol is used, there is no connection; each Terminal Server must be told
explicitly which hosts it is allowed to accept packets from. Each Terminal Server would
have to be configured to both send packets to and accept packets from the other Terminal
Server.
Serial Device
Serial Device
LES_B
LES_A
Ethernet
Ethernet
LAN/
WAN
Summary of Contents for 16-Port Rackmount 10/100
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