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Thursday, July 19, 2012

VMware vSphere Client - Error 503

I posted about this same error message sometime back but now I have discovered an easier and faster way to resolve it.  Not fix it permanently, mind you, but at least make it so you can connect to your vSphere server using the VMware vSphere Client.

The Problem
When you are trying to logon to your vSphere 5 server using the VMware vSphere Client you get an error that says, "The remote server returned an error: (503) Server Unavailable".

The Solution
Assuming you have enabled SSH on your vSphere server you can open a Putty session on port 22.  After you have connected and logged in as root, issue the command called dcui and this will launch a console session that looks just like you were standing at the server.

Click F2 and login as root

Choose Troubleshooting Options from the menu

Choose Restart Management Agents from the menu

Press F11 to confirm your choice

Once the services are restarted you should now be able to login using the vSphere Client.  

There have been times when I've had to restart the Management Agents multiple times before I could finally get the vSphere Client to work.  I was hoping this would be resolved with VMware vSphere 5 Update 1, but unfortunately it has not.  And this is only occurring for me on one vSphere server whereas we have five others that are behaving fine.


  1. Great post.

    Thank you. It works. (For ESXI v5)

  2. dcui didn't do anything for me via SSH, however /sbin/ restart did fix the above issue.

  3. Thank you so much! This worked perfectly for me (ESXi 4.1). Really helped us out.

  4. What a wonderful piece of information Admiring the time and effort you put into your blog and detailed information you offer! I will bookmark your blog and have my children check up here often. Thumbs up!

  5. Thumbs UP!! Great Post, I just wasted 1 hour of work trying to figure out what was wrong with server till I found your post! Thanks for sharing such helpfull info!!

  6. Thank you very much. This worked perfectly for me (ESXi 5.1)
    Very happy, keep up the good work David.

  7. thanks for the help!

  8. I'm trying it now & will give you my feedback :)

    I run this command many times
    /sbin/ restart

    & restart managment agent many times after it works with me:)

    Thnaks a lot. Now I will check the health of my VMs.

    Thanks again for all of you.