RAC0218: The maximum number of user sessions is reached
this happens when several people have not logged out their sessions - or may have forgotten about them. The obvious answer is to do it from the OS and Open Manage Server Administrator (OMSA) - but what if that is somehow unavailable (esxi, for example). Two levels of solutions without resetting the drac settings:
1) if you are lucky, establishing a SSH session will allow you to login. issue the drac soft reset command to regain web access (racadm racreset soft, press enter, wait for pings to go away and come back)
2) if the SSH session tells you it's also out of sessions (in a message similar to " Server sent disconnect message type 11 " you can still reset the drac without power cycling the server, but need physical access to the server. Hold the i button on the back of the server approximately 20 seconds (until the drac stops pinging). This is a hardware initiated drac soft reset.
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Upgrading drac firmware fails at 30% (seems more common on generation 11 dell servers (r710, r610) and early versions of firmware)
What solved it for me was finding a server that still ran internet explorer 6. You have to remember that new browsers were not supported until X moment of time and firmware revision, so always test with browsers available at the time the firmware was released, or different browsers. A friend of mine swears firefox always works.
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Java, you pain in the butt.
The best version of java for accessing Dell stuff (compellent support actually told me this tip) is version 7 update 45, both x86 and x64 versions. It still prompts if you want to upgrade java or do it later, and still runs everything.
If you don't like this solution, and want to use the latest Java, you can do two things:
1) add the drac url to the java trusted sites (Control Panel, Java, Security tab). this is probably the best way to go.
2) lower Java security to the minimum from Control Panel, Java, Security tab
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After upgrading the drac's firmware, you get
JAR resources in JNLP file are not signed by the same certificate
The solution to this is to open Java in Control Panel and delete the Temporary Internet files :p
I will add as I find from my own experience.
