I recently ran into an issue where the DRAC on an R610 froze up when the OS became unresponsive.
The system is running VMware ESXi 4.1.0 (Dell version) and froze up, and I'm not sure why. When I tried to connect to the DRAC, it was also unresponsive. I am using the dedicated NIC for the DRAC, and was able to ping the IP address but not connect via https or ssh. My only option was to hard remove power using our remote power switch.
The point of the DRAC is to be able to remotely access the system when the OS is not functional. If an OS component can take down the DRAC, it calls a lot of recovery plans into question and I have lost a bit of faith in the DRAC. I have seen this before when sharing the network port with the OS, but not when using the dedicated NIC.
The iDRAC is not a completely independent computer system. Some of the functionality like video processing requires system board components. If the DRAC is not accessible when the lockup occurs then I would lean toward the lockup being hardware related, or a software issue causing a hardware lockup. I would suggest checking the hardware logs for any events coinciding with the lockup.
Let me know how it goes.
Dell EMC, Enterprise Engineer
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Given a hardware issue with video or other integrated component, I would not expect to be able to access that component, but for the entire DRAC to be unresponsive is worrying. I rely on DRACs to be able to remotely reset systems in such a case. I can't blame the DRAC if the DRAC itself is faulty, but other faults shouldn't affect it.
I performed the Dell hardware diagnostics and it did not find any issues. Also, before this occurred, we had received a spurious alert from our monitoring system where all sensors seemed to disappear for a moment. Since a firmware update and reboot, the issue has not returned.