[lug] Help using Serial Console

[Sean Reifschneider]

On Mon, Jul 23, 2007 at 12:08:00PM -0600, George Sexton wrote:
>Next year, I buy an IP based KVM....

In the past I've recommended the StarTech SV1110IPEXT which is a 1 KVM port
box that runs Linux and you can VNC to for console access.  It's worked
pretty well for us.  You then connect it to something like the 16-port 1U
Startech KVMs which can let one of the IP boxes control something over 100
machines.

However, they recently upgraded the model of the 16-port KVM to support
USB, and either that or the newer firmware on the IP box on a new
deployment were nearly worthless if you cascade them.  It works passably
well if you just connect a single 16 ports and don't cascade.  I tried
working with Startech but it basically boiled down to them saying the next
step was for them to get logged into this KVM to look at it.  So, I'm going
to have to get a test environment set up for them to try.

Perhaps they will resolve it, but a previous technical support request I
had with them about the new model of 16-port box was pretty unsatisfactory
resolution.  They didn't actually try to fix anything, just suggested that
if it didn't work with an older KVM cascading to the new one that I switch
them around and see if that works.  I mean, is it supported to cascade them
that way or not?  If it's supported, why aren't they fixing it?  Swapping
the 16-port primary KVM for a new one is a kind of big freaking deal,
probably several hours best case which I'd prefer not to do.

In the end I just delayed the problem by tracking down a few of the old
model 16-port KVMs and buying them.  Once we run out of ports on this
cascade set though, we may have to find another IP KVM solution.

The nice thing is that this box uses VNC for getting access to the console,
so you don't need any Java plugins (or worse, Active X), you just run
vncviewer.  It also does SSH, so we have VNC tunneled over SSH (tunneled
over OpenVPN, of course :-).

The other nice thing is that the IP KVM box is only like $500.  The 16-port
1U box is something around $400, and cables are CHEAP, a few bucks each.
Though, they used to have 2 and 3 foot cables that were REALLY nice for
cabinets, now the shortest they have is 6 foot, so a lot of cable wrapping
up to do.

I'm starting the process of evaluating the Supermicro remote management
cards, which seem to be reasonable.  They're around a $100 card that gives
you remote access to reset the system (right now we use an IP connected
power strip to power cycle the box, reset would not cause a loss of power
to controller boards and stuff which may be a big deal if you don't have
BBUs for RAID cards), and it gives you access to the console.  However,
this console access is via a Java applet.  Would be great if it were just
VNC, but VNC is not proprietary so the vendors don't like it.  :-(

You also get the ability to power the server off *AND* on (which the remote
power strip does not give you, if for some reason someone hard powers the
system off or it otherwise doesn't come back on when AC is restored (some
BIOS bug I've seen caused that), you're stuck.  This board also gives you
access to the sensor data and can send alerts via e-mail or SNMP or syslog
IIRC.

The down side is that this $100 board that includes KVM support only works
with the more expensive Supermicro servers.  Even the cheaper machines that
take this same card say "Motherboard does not include KVM connections to
this card slot".

So far I've done limited testing, but it looks good.  Other than taking
4-ish months to get the right card in...  It's model is a mumble-plus, and
most places don't carry it.  One of our vendors listed the mumble-plus
card, but then changed the order to the mumble board behind the scenes
because they had problems getting the mumble-plus.  The +, of course, means
that it does KVM.  Argh.

I have also played with the HP ILO a bit, and it's pretty nice.  If your
console is just text, you can just SSH in to it and interact with the
console.  If it goes graphics, you have to use a Java applet.  Our servers
run pretty much only text consoles, so that's nice.  You can also do power
on/off/reset, but I don't recall seeing sensor data easily available.  I
didn't dig too much though.

Anyway, that's what I know about remote KVMs.  I hate the big name ones,
they all have proprietary clients.  One of our clients has one that pretty
much every page on the vendor site says "Linux support!" except for this
one that ways "Linux support!  *"  Where the * footnote is "Linux support
not currently available."  Maybe the world has changed since I researched
and found the Startech, but there was little choice back then for VNC KVMs.
Which is a shame.  Serial sucks, but is better than nothing I guess...

Sean
-- 
 The only people who have anything to fear from free software
 are those whose products are worth even less.  -- David Emery
Sean Reifschneider, Member of Technical Staff <jafo at tummy.com>
tummy.com, ltd. - Linux Consulting since 1995: Ask me about High Availability