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Network connection lost after vCSA restore

Today we encountered a strange error after restoring a vCenter Server Appliance (vCSA) in our vCloud Director environment.No_Connection

You would expect that a restore of a virtual machine would return it to its original state at the time of the back-up.  As it turns out this is not the case when restoring a vCenter Server Appliance (vCSA), vSphere Data Protection (VDP) Appliance or vSphere Management Assistant (vMA).

The first thing we noticed was that it took a very long time (10 minutes) for the vCenter Server Appliance to start up. This is very unusual because with the underlying hardware and the reserved resources this would normally take less then a minute. When finished the console shows ‘NO NETWORKING DETECTED. Please configure your network.‘ So Network connection lost.


You will notice that the console also shows no IP address and  to manage the appliance you should connect to (good luck with that).

The reason that there is no network connection is quite strange. The restore of the vCenter Server Appliance did return it to its original state at the time of the back-up, but for some strange reason a new MAC address is generated for the appliance. The MAC address is stored in a configuration file that does not get updated with the new MAC address, which causes the appliance to not be able to find the correct NIC. The operation creates a new UUID and so a new Mac Address is assigned for the virtual NIC. As a result the virtual NIC is now detected as ‘eth1‘ rather than ‘eth0‘.

Eventually we found VMware KB article 2012451 which describes how to resolve this issue on the vCenter Server Appliance (vCSA), vSphere Data Protection (VDP) Appliance or vSphere Management Assistant (vMA).

To resolve this issue on the vCenter Server Appliance:

  1. Right-click the vCenter Server Appliance Virtual Machine and click Edit Settings.
  2. Click Network adapter 1 and record the new MAC Address value. Click OK.
  3. Power on the vCenter Server Appliance and click the Console tab.
  4. Log into the vCenter Server Appliance with root credentials.
  5. Change directory to /etc/udev/rules.d/:cd /etc/udev/rules.d/
  6. Back up the /etc/udev/rules.d/70-persistent-net.rules file.
  7. Open the /etc/udev/rules.d/70-persistent-net.rules file in a text editor, and change the MAC address to the value recorded in step 2 for eth0. For example:SUBSYSTEM==”net”, ACTION==”add”, DRIVERS==”?*”, ATTR{address}==”00:50:56:aa:52:39″, ATTR{type}==”1″, KERNEL==”eth*”, NAME=”eth0″
  8. Comment out the line corresponding to the eth1 interface.
  9. Save and close the file.
  10. Restart the vCenter Server Appliance.

After the restart our vCenter Server Appliance is up and running again.


Erik Scholten is the founder of VMGuru and works as a Specialist SE for SDDC at VMware Benelux. He has over 17 years experience as a system/network engineer, consultant and Solution Architect and he specializes in virtualization. His current job includes selling, presenting, designing and developing virtual infrastructures for some major companies in the Netherlands. Erik is a certified VMware VCP (3, 4, 5, 6), VCP Desktop (5), VSP (3, 4, 5, 6) and VTSP (3, 4, 5, 6). In 2009, 2010, 2011, 2012, 2013, 2014, 2015 and 2016 VMware awarded him the vExpert award for his virtualization community efforts. In 2014 Cisco also recognized him as a Cisco Champion .

  • smitmartijn

    Deleting both entries and rebooting is faster. 😉