IPMI has been turned on for the Dell nodes.  Interacting with them is quite simple.  From a machine connected to the cluster on the internal interface you can query and control the chassis of the Dell nodes, regardless of the state of the OS on the machine.  (Thus a crashed machine can be restarted without need for UPD intervention.) You can also check sensor status and chassis voltages.  All-in-all its a really great feature of the Dell machines.

The IPs of the ipmi interfaces are different than the nodes Linux IP, even though they share a physical connection to the switch (also very nice, since we didn't have to run 2 net wires.)

These interfaces live at:

172.16.2.61 - 172.16.2.111

(on the headnode these are mapped to ipmixxx in the hosts file)

The last number indicates the WN's queue spot.

Logging into the chassis is quite simple.  Use the  ipmitool utility (ipmitools are installed on red)

 ipmitool -U root shell -H 172.16.2.xxx

or

ipmitool -U root shell -H ipmixxx  (on the headnode)

Give the node's ipmi root password, this is different than the root password for the nodes.

You should then issue a 'chassis status' to make sure your connected.  I found the impitool does not check to see if you are in fact connected before giving a prompt.  You should see something like:

ipmitool> chassis status

System Power         : on

Power Overload       : false

Power Interlock      : inactive

Main Power Fault     : false

Power Control Fault  : false

Power Restore Policy : always-off

Last Power Event     :

Chassis Intrusion    : inactive

Front-Panel Lockout  : inactive

Drive Fault          : false

Cooling/Fan Fault    : false

Sleep Button Disable : not allowed

Diag Button Disable  : allowed

Reset Button Disable : not allowed

Power Button Disable : allowed

Sleep Button Disabled: false

Diag Button Disabled : true

Reset Button Disabled: false

Power Button Disabled: true

To restart the chassis (reboot the machine) issue the 'power reset' command.

To view the sensor output, issue a 'sensor' command.

The impi interface has a nice online help.