To connect to iLO serial port:
<code>
ipmitool -I lanplus -H <ip> -U <username> sol activate
</code>

To power on machine:
<code>
ipmitool -I lanplus -H <ip> -U <username> chassis power on
</code>

Or to connect with SSH
<code>
ssh -o HostKeyAlgorithms=ssh-rsa ilo-hostname-or-ip
</code>