IPMI Console Access
Contents |
Dell Blinking Lights
How do you find out what those blinking orange lights on the Dells mean?
How do you turn those alert lights off?
This is actually extremely simple and any NOC tech can easily investigate what events caused those indicator lights to come on, review the logs and then (if appropriate) turn them off.
The Console Access and IPMI commands below tell you exactly how to do this. It takes only minutes.
IPMI Rocks the House
IPMI allows you to monitor many aspects of server operations and status as well as issue various control commands. This can be done regardless of the state of the OS - even if the system is locked in a kernel panic you can still access IPMI as it is a separate service processor.
Remote Access
(Just for your information.)
Normally, you configure IMPI in BIOS by giving the server an IP to use on its IPMI interface which is actually an "invisible" NIC used exclusively for this purpose. This NIC then shares one of the physical Ethernet ports. For example, the Dell servers have two Ethernet ports and two Ethernet interfaces - but they also have a third Ethernet interface that is used for IPMI and this shares the first Ethernet port.
Of course you can configure IPMI so you can remotely connect to the server and issue IPMI commands (reboot, view the error log, view various monitors for temperature, fans, CPU voltages, etc.) but this requires configuring IPMI on the server and then connecting to it over the network. You can even run a remote shell session by connecting via IPMI using Serial Over LAN. This is not particularly difficult and there is a separate detailed wiki on how to do this here: IPMI Configuration and Monitoring
Console Access
Even Easier!
Because setting up remote IPMI access involves several steps and can be time consuming you can also employ direct, local console access using impitool. This allows you to run ipmi commands locally and even enter an interactive IPMI shell, etc. Setting this up takes just a few minutes and is very easy. There are several ways you can do so, outlined below.
WAYS TO USE IPMItools
CentOS 5.2 Script
I have created a script that runs on CentOS 5.2 to help with this. You simply wget the script from:
wget http://ks.sagonet.com/ipmi/ipmi-install.sh
This downloads and installs all the RPMs you need, loads the kernel modules needed and gives you a pretty summary screen of what to do. It is extremely easy to use. You can install this on any box running CentOS 5 or higher and it should work fine. (CentOS 4.6 and lower need additional packages so in that case see the PXE solution below.)
This allows you to check and clear the IMPI logs and make IPMI configuration changes without ever having to reboot the server. Nice eh?
PXE Live Environment IPMI
Our normal PXE Linux live environment is RIP, and unfortunately this does not support IPMI.
However, you can also use the 'rescuecd' option from the first PXE menu. This environment has the ipmitool binaries installed and the kernel modules you need to use it, however they are not loaded by default.
To set this up to use IPMI is extremely use. Once you are at the command prompt simply type:
#modprobe ipmi_si #modprobe ipmi_devintf
You can run IPMI commands directly or enter the interactive shell - see below for examples.
Ubuntu Live CD
You should also be able to use a Ubuntu Live CD and install openipmi if needed and load the same kernel modules as above, though I've not tested. However, since you can use the PXE Rescuecd environment, it is suggested you use that rather than an actual physical CD. Those are SOOOOO last year . . .
IPMI Commands
Here are some handy IPMI commands to help you get started. There are a lot of things you can do with IPMI, but these are some ones we are most likely to use.
Remember, you can run commands one at a time like these, or you can just enter an interactive IPMI shell and use that. Use '?' for help in this shell and each of its modes and sub modes.
ipmitool -I open chassis power # Server power status ipmitool -I open sel list # Show the server event log ipmitoo - I open sel clear # Clear the log (turns off light on Dells) ipmitool -I open sdr # View all sensors, a LOT of info here ipmitool -I open shell # Interactive shell session, you might want to use this
OpenSolaris
Why can't I connect using ipmitool on opensolaris using:
root@opensolaris:~# ipmitool -I bmc -U root chassis status Could not open bmc device: No such file or directory
You use the bmc interface in Solaris, but the driver for this is restricted. For a work around, install the bmc files from a SXCE or SXDE or Nevada disto, or ip the interface in the BMC manager and connect with the lan interface, such as:
ipmitool -I lan -H SPs_IP_address -U root
Which comes from this bug report
Additional Solaris IPMI info can be foune here
