Hi ingfimo,
I have encountered the same problem on HP ProLiant DL140 G3. Could you please let me know what’s the password you set for the user maas on the IPMI of the HP machine? Thanks.
By checking this docs, it only said,
The MAAS-generated IPMI username is set to “maas” by default. This username is used for IPMI authentication.
but did not mention about the password.