Remote text based console to ESXi over IPMI SOL

I have just bought another server into my home lab. I already have 6 Intel NUCs but a lot of RAM is needed for full VMware SDDC with all products like LogInsight, vROps, vRNI, vRA, vRO, ...  but that's another story.

Anyway, I have decided to buy used Dell rack server (PowerEdge R810) with 256 GB RAM mainly because of the amount of RAM but also because of all Dell servers older than 9 Generation support IPMI which is very useful. The server can be remotely managed (power on, power off, etc.) over IPMI and it also supports SOL which stands for Serial-over-LAN for server consoles. IPMI SOL is an inexpensive alternative to the iDRAC enterprise virtual console.

You can read more about IPMI on links below

• IPMI SOL – Inexpensive Remote Console
• Fun with ESXi, IPMI and Dell BMC/iDRAC – Remote Power Cycle, Console and more
• impitools

So, if you will follow instructions on links above, you will be able to use IMPI SOL to see and manage server during the boot process and change for example BIOS settings. I have tested it and it works like a charm. You see the booting progress, you can go to the BIOS and change anything how you want. Console redirection works and the keyboard can be used to control the server during POST. However, after the server POST phase and boot loading of ESXi, the ESXi console was not, unfortunately, redirected to SOL. I think it is because ESXi DCUI is not pure text based console. Instead, it is a graphics mode simulating text mode. A graphics mode consoles cannot be, for obvious reasons, transferred over IPMI SOL.

So there is another possibility. ESXi Direct Console (aka DCUI) can be redirected to a Serial Port. The setup procedure is nicely described in the documentation here. It is done via ESXi host advanced setting "VMkernel.Boot.tty2Port" to the value "com2". It is worth to mention that server console redirection and ESXi DCUI redirection cannot be done on the same time for obvious reasons. So I have unconfigured server console redirection and configured ESXi DCUI redirection. It worked great, but the keyboard was not working. It is pretty useless to see ESXi DCUI without the possibility to use it, right? To be honest, I do not know why my keyboard did not work over IPMI SOL.

So what is the conclusion? Unfortunately,  I have hit another AHA effect ...

"Aha, IPMI SOL will not help me too much with remote access to ESXi DCUI console."

And as always, any feedback or tips and tricks are more than welcome as comments to this blog post.

Update: I have just found and bought very cheap iDRAC Enterprise Remote Access Card on Ebay, which supports remote virtual console and media. So, it is hardware workaround to my software problem :-)

iDrac6 on Ebay

FreeBSD with multiple Serial Adapters acting as Access Console Server

I play a lot with network equipment like switches, routers and firewalls. It is very useful to have local serial access to consoles of such devices. When I say local, I mean remote access to local serial console. I can use some commercial Access Console Servers from companies like Avocent but these devices are usually very expensive and don't do anything else than linux box with multiple serial ports accessible remotely via ssh or telnet.

So my idea was to use my favorite unix-like system (FreeBSD) with multiple serial ports. For such appliances I usually use Soekris or Alix boards with FreeBSD on Flash. The question is how to have multiple serial (RS-232) ports. The simplest method nowadays is to use usb serial adapters. I know these usb serial converters has some issues but it is really the simplest peace of hardware to buy, plug and play.

When you use some of these USB converters you should see new devices. In my case I see in dmesg following devices:

uftdi0: on usbus1
uftdi1: on usbus1
uftdi2: on usbus1
uftdi3: on usbus1

To make serial console working you have to load uftdi module. uftdi -- USB support for serial adapters based on the FTDI family of USB serial adapter chips.

The easiest way is to load this module during boot. You just need to add to /boot/loader.conf following line

uftdi_load="yes"

After next boot you will have following new devices in your /dev/ directory

/dev/cuaU0
/dev/cuaU1
/dev/cuaU2
/dev/cuaU3

 ... and you can use program cu to connect to particular serial console. For example

cu -l /dev/cuaU0 -s 9600

to connect to console with speed 9600 bauds.

Soekris NET4801-48 with USB reduction to 4xRS232