Using ipmitool @SuperMicro server

It' about time using IPMI instead of KVM-switch. In fact this capability is all the time there in our servers. Don't ask why I did not do this from the beginning.
Anyway, this is how to redirect console output to serial over lan (SOL), and controlling power via IPMI.
In fact a SuperMicro server has already embedded IPMI in the mainboard, which is accessible using http connection (Luckily its true for me). It has as well a KVM over ip facility, using java's iKVM. But, this java dependency is not so "flexible" for my need, regarding the fact that java plugin does not (currently) always work (particularly in x64). I think console application is still the perfect tool. So, I put my eyes to impiconsole and ipmitool.

Before using remote management, first you have to do some BIOS settings. This figures explain those settings, quite clearly:

Remote access settings 

IPMI IP settings

Notice that COM3 must be used to make SOL works properly.

After all the settings are correct, you may direct a browser to the specified ip address, and the server can be fully controlled using browser. Console redirection will work if java plugin is configured correctly (under "Remote Control" menu).

Now install ipmitool and freeipmi-tools on the managing server (client, or whatsoever):

apt-get install ipmitool freeipmi-tools

Ipmitool is used for controlling/managing the server. It has a complete set of instructions. In fact, only "power on" and "power off" command are the most useful ones. Example:

ipmitool -H 192.168.0.100 -U ADMIN -P ADMIN power on

to power on the unit. ADMIN and ADMIN is the default user name and password.

To enable access using SOL, the following configuration must be done:

1. @/boot/grub/grub.cfg add this:

serial --unit=2 --speed=115200 --word=8 --parity=no --stop=1
terminal --timeout=10 serial console
and add "serial console=ttyS2,115200n8" to the "linux" line.

Don't use splash!
(Yes, grub2 configuration file looks a bit weird...)

2. @/etc/inittab add this:

s0:2345:respawn:/sbin/agetty ttyS2 115200

3. Make sure that ttyS2 is listed in /etc/securetty

Thats it. Now call:

ipmiconsole -h 192.168.0.100 -u ADMIN -p ADMIN

and boot the server. This is more or less the console output from the server:

For installation purpose, ipmiconsole is good if the installation media is able to redirect its output to the serial port. If not, the iKVM konsole (http access) is better, since it does not need any COM port at all.
This ipmitool command has the same function as ipmiconsole:

ipmitool -I lanplus -H 192.168.0.100 -U ADMIN -P ADMIN sol activate

See manual page of ipmitool and ipmiconsole for more complete reference.

One good thing from this server that IPMI may use a network wire together with the first interface (eth0), so I can use one less cable. Indeed, a separate RJ45 connector is also provided. In the client side I used multiple address in one of interfaces. Embarrassingly, I found it out recently that this is so easy to configure in Linux.

Say, in the admin computer (actually the main server) you have eth0 as your main interface, and is connected to the real ip address in the network. Since the network cable in the server (node) is used together by IPMI and the main interface, both are plugged into the same hub connection. Normally we need two interfaces plugged to the same hub at admin side.  Uneconomical indeed.
The better way is using multiple address for a single interface. After bringing eth0 up, bring another interface, eth0:0, as example:

ifconfig eth0:0 192.168.0.1 netmask 255.255.0.0

In debian system, one can put in /etc/network/interfaces:

auto eth0:0

iface eth0:0 inet static
address 192.168.0.1
netmask 255.255.0.0

Now the first interface can be used both to access the internet with its original address (eth0) and also for connecting IPMI devices in 192.168.0.0 network.
For mac user, multiple address in a single interface can be easily configured in "Network Preferences".