Can't use "eject" to identify the server
I'm a software engineer and our lab usually has several servers in a rack with a KVM switch. We're developers and we usually have several projects happening at once so the servers are frequently imaged and admittedly we aren't good at keeping them labeled, etc.
The point is, up until recently, as soon as we walked up to a terminal it was our habit to use eject to see which physical server we were actively selecting on the KVM switch, for obvious reasons.
Now we are transitioning into servers without optical drives. So the old eject trick is obsolete. There must be a simple command to flash the "ID" indicator on the front panel of the computer, but after Googling as many variations of the question as I could think of, I got nothing.
The servers are running Scientific Linux 6.4. Thanks for any help you can offer.
Most modern servers come with an out-of-band management option, eg HP's ILO, Dells DRAC, IBM's RSA, so you don't actually need to go to the rack anymore to manage them. Simply use the correct form of KVM over IP to take over the console from the comfort of your desk!
They come with virtual media which uses an ISO image on your desktop to emulate an CD/DVD drive you can install from. Virtual power switches to power up, down or reset the server and more.
The out-of-band management card has it's own independent IP-address from the server it is managing. So label the actual servers and and give the out-of-band management card the same name and you'll see the current hostname of the OS once you take over the console.
And oftebn the out-of-band-management card allows you to light an identification light for the rare cases you do need physical access.
I also love eject! anyway, you need to check support package from your server vendor.
for example, HP provides a command line utility to check/set/unset UID LED for their proliant servers. and iLO, HP's remote management tool, provide same function.
If your out-of-band management does not allow you to flash the indicator, you could try ethtool if you have a spare/empty network interface
ethtool -p eth2
Should flash the LED for eth2:
-p --identify Initiates adapter-specific action intended to enable an operator to easily identify the adapter by sight. Typically this involves blinking one or more LEDs on the specific network port.
Then you can go search the server with an empty but blinking network interface. This should also work for interfaces that are up and running (if they're all connected), but then you'd have to distinguish between the ethtool regular interval and the normal blinking that shows the interface activity :)