you can restart the DELL iDRAC over ssh when you cannot connect over the html web management page with
racadm racreset soft
To do so, connect over SSH to the iDRAC and run the racreset
# ssh hostname-idrac -l root
root@hostname-idrac's password:
/admin1-> racadm racreset soft
RAC reset operation initiated successfully. It may take a few
minutes for the RAC to come online again.
/admin1-> Connection to hostname-idrac closed by remote host.
Connection to hostname-idrac closed.
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