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ipmitool will ask for a password for user ADMIN in all cases. You can avoid this by putting it in a 0600 file and using the -f flag, or passing it on the command line (-P; not super-secure, but our environment is pretty trusted), or putting it in your environment (see the man page).
IPMI View
SuperMicro distributes a multi-platform Java GUI app called "IPMI View" that incorporates the above functions, and more. It's a bit slow and not amenable to scripting, but it does support the KVM console, which can be very useful. Note that your machine will have to be on the internal cluster VLAN to access the ipmi controllers.
IPMI View can be obtained at ftp://ftp.*supermicro*.com/utility/*IPMIView*/
What's the ipmi password?
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