Random hangings of i DRAC7 on R620 when you can't connect to it remotely either via ssh or HTTPS proved to be very consistent if you access DRAC with large intervals.What Dell (unlike HP and CISCO) did right is that on rack servers like R620 and R720 it provides a button with the letter i on it (i-button) to reset DRAC on the front panel of the server.Looks like you cannot reset the i DRAC using ipmitool.You can do it using either This RACADM tool provide command line interface allowing to script set-up and update of DRAC.From Google search on the topic it is clear that this problem exists since the release of DRAC7 at the beginning of 2013. The problem is acute only for remote servers without any qualified personnel to access the server.From Google search on the topic it is clear that this problem exists since the release of DRAC7 at the beginning of 2013.
This is so similar to ILO 3 behavior that I suspect that both Dell and HP licensed the codebase from the same source.
So it you have a lot of identical or similar Dell servers (for example Dell enclosure with 165 blades) it has additional value as automation tool for routine operations In case you don't have personnel on a remote site this is a disaster and big SNAFU for DELL.
In the rat race for additional functionality they forgot the primary purpose of the DRAC -- to be reliable KVM -- and the main criteria of its usefulness -- reliability.
Blades are not affected as DRAC in blades can be rebooted from the enclosure controller.
This is essentially the same blunder as as HP SNAFU with i LO 3 -- often So you have the situation, when the last time you use DRAC it was OK, then the next time, in a month or two you can't connect.