Re: [SAGE] DTE: PCMCIA card which emulates a monitor?

[Joseph Noonan <joseph.noonan@rigaku.com>]

On Fri, 16 Nov 2007 at 11:38am Richard Chycoski wrote:
>
> This still doesn't give you the real 'console' of the server. I've tried 
> using the serial consoles on some of our servers, but there are cases where 
> only the real (at least VGA+kb) console will do. This is why I set up a 
> KVM+KVM->IP combination in my lab for the Linux and Windows servers. (I'd 
> like to get one for my lab at home, but I don't want to spend the $$$.)
>
> For machines that have true lights-out management, you don't need to do this, 
> it can all be done on the network (true lights-out mgmt included 
> KVM-over-IP).

Right, I use Dell servers and they have a product called DRAC (Dell 
Remote Access Controller) that has gotten better over time (the versions 
II and III were pretty bad).  They're not great and they frequently 
remind me of the days when I used VNC to admin remote Windows servers, 
and that is probably no coincidence as they run some embedded version of 
VNC.  (On a side note, I switched to Netopia's TB2 from VNC a long time 
ago for working on Windows remotely because VNC was so flaky.  TB2 is 
very good, very reliable, and has built in support for tunneling over 
ssh.  However, it has some proprietary file transfer protocol that is 
incredibly slow.  I mean, truly, unbelievably slow.  Speeds in the kbps
range over GB ethernet. I never use it.)

> If you have machines that have well-behaved serial consoles (e.g., 
> Suns) you can use the serial trick. Instead of a multiple serial port 
> to USB converter, you can use a terminal server with ports connected 
> to all of the consoles. Then run 'screen' from a central concentrator 
> host to each of the terminal server ports, and any sysadmin can 
> connect to that host and get to the console of any connected machine.

Ah, yes, well behaved serial consoles: brings back memories of loading 
VAX/VMS from the serial console over a 9600 baud modem. :-).  But I no 
longer run VAXen, Alphas, or SGI's with serial consoles -- it's not that 
I run windows everywhere, it's that I run stuff on machines designed 
(mostly) with Windows in mind: Intel x86 based servers.

I like to use Paul Vixie's rtty and screen on FreeBSD 
(ports/sysutils/rtty) with a multi-port serial card.  I have an old low 
profile Pentium (I) era PC, with a Digi 32 port serial card that I 
scavenged from a decommissioned AlphaServer 500.  I plug my serial 
consoles (routers, witches, power controllers, temperature sensors) into 
those ports.  You then run the rtty 'console' command on each port with 
something attached to it at boot, then you can ssh in, run screen, and 
attach one console per screen window.  Console takes care of all the 
logging w/o having to run screen manually, but running screen manually 
the first time you login makes it nice for subsequent logins.

> It's not hard to set up a script to keep the terminal server connection live 
> and if all else fails you can connect directly to the terminal server from 
> your remote connection.

rtty will do all that for you and multiple people can attach to the same 
console session simultaneously.


Cheers,

-j




-- 

Joseph F. Noonan
Rigaku Americas Corporation
joseph.noonan@rigaku.com