Use IPMI tool to change HP ILO 100 password from Xen Server

List all the users
# ipmitool user list

output:

ID  Name             Enabled Callin  Link Auth  IPMI Msg   Channel Priv Limit

1                    true    true    false      true       ADMINISTRATOR

2   Operator         true    true    false      true       ADMINISTRATOR

3   admin            true    true    false      true       ADMINISTRATOR

4   OEM              true    true    false      true       ADMINISTRATOR

5   Operator         true    true    false      true       ADMINISTRATOR

6   admin            true    true    false      true       ADMINISTRATOR

7   OEM              true    true    false      true       ADMINISTRATOR

8   Operator         true    true    false      true       ADMINISTRATOR

Change the password for user 3

# ipmitool user set password 3 <PUT THE PASSWORD FOR USER#3 HERE>

Enable user 3.

# ipmitool user enable 3

Set user 3 to administrator rights

# ipmitool user priv 3 4

Now log in from the web console.