Review: Lightwave Communications CS800
For the first product review of the new year, I’ll be taking a look at the
ConsoleServer 800 from Lightwave Communications. This is a 1U rackmountable
8-port serial console server, packed full of features.
Until I ran across the CS800, I’d never used a “dedicated” console server
before (e.g., one *designed* to be a console server). I’d always used
equipment such as a Lucent PortMaster or a Cisco AS5200 (designed to be
remote access servers with modems attached) with rigged-up serial connections
to the equipment I wanted to reach remotely. Unfortunately, doing it that
way had a few problems:
sent – dropping Sun systems into OpenBoot
Then, in late 2001, I ran across
Lightwave Communications. I’d used one of their other products before
at my “day job” – the ServerSwitch, and had been very happy with it. I had a
need for a serial console server for the SunHELP servers (and some other
machines that sit in the same rack), so I took a look at the ConsoleServer
800. The folks there were kind enough to send me a unit for review, as
well as a ConsoleServer 3200 and a 2-port ServerSwitch.
The CS800 has a 1U (rackmountable) form factor, uses a standard power cord,
and has RJ45 ports for serial cable connectors (as is now pretty much
standard across the industry – this saves space on the console server end
of things). All the ports are on the back, while the front has the product
and company name/logo, with a backlit status-display LCD and some membrane
“buttons” to control the LCD. Ports on the back, from left to right
(see picture link below):
The CS800 is available with -48VDC power supplies instead of AC, and the
modem module is optional. I was not able to test the functionality of
the modem module on my review unit, due to lack of an available phone
First thing I really liked: The users manual and updated firmware for
the CS800 are available from Lightwave’s FTP site. When I misplaced the manual, I just went to
the FTP site, downloaded it again, and was ready to go (I later found the
one that I had lost). Pinouts for all of the ports on the CS800 are detailed
in the user manual, in case you want to “roll your own” RJ45-serial connectors
instead of purchasing them from Lightwave along with the console server.
Firmware upgrades on the CS800 are performed via TFTP over the network.
My first use for the CS800 was setting up one of the new SunHELP servers,
which went online in early November (yes, this review has taken a while to
writeup and get online). Lightwave supplied plenty of RJ45-to-DB25 adapters
(as shown in the picture), so all I had to do was connect a normal straight-
wired Cat5 (cat3 would also work, as this is just 9600 baud serial) cable
between the adapter and the RJ45 port on the back of the CS800.
Interfacing to the CS800 can be done either through telnet, or a directly-
attached serial console. I used a nullmodem connection between my SunBlade
1000 and the CS800’s console port to do initial setup and TCP/IP configuration,
then used it from then on through a telnet session on the local network.
The front-panel LCD display can show either software version, port use
status (showing what user is logged in either over the network or through
direct-connect serial), or TCP/IP configuration information. This is
toggled via the buttons on the front of the unit. The LCD is backlit and
is very viewable (see pictures below).
The CS800 also includes a “power controller” port, which is basically just
another serial port, but with a DB9 connector. With the right cables, you
can connect this to a normal device as well instead of a power controller
serial connection, and use it just like the RJ45 device ports, making the
CS800 into a 9-port console server.
Something I didn’t like: The ethernet port (RJ45) on the CS800 is
10baseT *only*. This is noted in the manual, which states that you *MUST*
plug it into a 10baseT network connection, and that 10/100baseT autonegotiating
ports on a hub or switch will *not* work. I tried and verified this fact
with a Cisco Catalyst 1900 switch as well as a NetGear 10/100baseT switch;
the network port only works when plugged into a 10baseT half-duplex link.
This is a severe hindrance, as when I later put a CS800 into production use
with the SunHELP servers, I had to daisy-chain it off of a 10baseT ethernet
hub that was then plugged into the same 10/100 switch as the rest of the
machines. Having to dedicate a 10baseT hub to correct a product limitation
such as this is not good, when I suspect a 10/100baseT chipset (or at least
one that can autonegotiate enough to tell a switch to go to 10baseT half-
duplex) would not have been much more expensive than what was used.
When logging into the CS800, you log in either as a normal user, or
as the administrator. All access is authenticated; in fact, I could not
find a way to give someone “free and open” access to the unit, which is
a good feature. The Administrator only logs by telnetting to port 5000.
This is another good feature, as Administrator access could be firewalled
off from the Internet, for example, only allowing “normal” users to telnet
to the server on port 23. The Administrator account is not able to access
device ports; it is only used for creating and managing user accounts and
system settings. Therefore, you have to create at least one user account
in order to use the CS800 for its intended purpose. According to the manual,
it is also not possible to obtain access to the administration functions
via the modem connection – I’m guessing this is for security reasons.
The CS800 does not have a Web-based interface like so many products these
days; all interaction is done through a command line or a Curses-based
“menu”; in either case, its straight text. After login (see links
below for pictures of the various admin and user login, help, and
device menus), you can press CONTROL-D to get the menu-based CURSES
interface, or continue to use the line-by-line interface.
Unlike the process of using an access server as a console server
device, the CS800 allows up to six concurrent people to be logged in,
all viewing the same console output at the same time. Only one person
can be fully interactive with the console, the rest can just “listen”,
or watch the device. This allows a configuration where a tech support
employee could watch console logs from a router or server, without having
to worry about generating keystrokes or codes that could hang or stop the
device in question. Each port has a 64-kilobyte scrollback buffer, and
50 separate user accounts can be created.
Each user account can have the following parameters:
Being able to restrict a user to certain ports is very useful. After
installing a CS800 with the SunHELP servers, I still had two (out of
eight total) device ports free. I was able to connect them to a
pair of servers at OnRamp, and add
an “onramp” user account that only had access to those two ports.
This allows OnRamp employees to have direct console access to their
systems, but no access to my six devices. However, I can still walk
up to the direct-attached serial terminal in the next rack over, or
connect via telnet, and login with full access to the device ports
that my systems are connected to. I mentioned before about other
terminal servers generating unwanted BREAK signals; the CS800 is
designed to only generate a BREAK when instructed; the default key
sequence for this is ESC-B, which is fully customizable.
Another thing I didnt like: When using the fancy CURSES-based
menu interface, the cursor dissapears. This persists even after you
exit a menu and connect directly to a device – making things such as
text editing very painful without being able to see the cursor. This
problem doesent exist when ONLY using the direct-command-line interface.
Tested and replicated this problem using xterm and rxvt, as well as a
genuine DEC VT510 terminal directly attached to the console port of
NOTE: (12/8/03) This problem has gone away in a later version of the
Other than the ethernet requirements and dissapearing cursor problem
(which will hopefully be fixed in a newer firmware release), I’ve never
had a single problem with the CS800. Its never hung, locked up,
spat out garbage, etc. I’ve got it connected to a pair of E250s, an
AXi-based SPARC machine, two SunFire 280Rs, and a Netra T1 (Lightwave
sells an inline RJ45-to-RJ45 adapter instead of an RJ45-DB25 adapter
for devices such as the Netra T1/X1 and Cisco networking hardware that
use an RJ45 console connection).
I like it. A lot. So much that I now have one sitting permanently at
the top of the rack of SunHELP equipment in downtown Austin. Its saved
me a trip downtown (a six-mile drive) many times now in the past two months
of service, and I wonder why I didnt get one sooner. The couple of limitations
I found are easily worked around or ignored and not an impact on what users
I need the CS800 for.
I dont have a goofy “star” rating, but I will say that the CS800 is
highly recommended. If you have a need for a good, quality serial
console server, the CS800 will work great for you.
Communications for more information or to purchase a ConsoleServer 800.
NOTE: (12/8/03) Since this review was originally published,
Lightwave was acquired by Lantronix,
and the CS800 has since been discontinued. It is still available from
Note: I also took a look at the ConsoleServer 3200, a 32-port version of
the CS800. Differences between the two:
Other than these differences, the CS800 and the CS3200 operate basically the
same from an administration and end-user point of view.
January 24, 2001