While attempting to upgrade an SDX from 12.0 to 12.1 using the Single Bundle Upgrade (SBU), the version of XenServer may not upgrade and remain at 12.0.0-89, with the SVM upgrading to 12.1

The goal is to run the SBU, so that the XenServer upgrades to the relevant version

In case of Single bundle upgrade failure, the Dom0 partition disk space Use% gets stuck at 100%. This is sticky condition and can only be corrected by rebooting the SDX appliance. Once the system reboot is complete, the disk Use% should drop back to normal. A check can be performed by the df / command as described in previous section.

Loss of space can be attributed to the amount of logs accumulated in the /var/log directory on the file system. Bringing down the Use% to 72% will allow the SBU to succeed,  perform the following steps:
 

1. Reboot the system to get it out of 100% sticky mode

2. Run the following command on XS/Dom0 console to cap the log rotate to 200 Mb instead of 500 Mb
   sed -i.bak 's/500/200/' /opt/xensource/bin/delete_old_logs_by_space 

3. Wait for minute or so for log rotate to kick in an do the necessary clean up and reduce the accumulated logs to around 200 Mb. 

4. Verify that the XS/Dom0 partition available disk space Use% is less than 72% for upgrade to succeed.

5. Run the SBU again. 

Problem Cause

Attempting to upgrade an SDX, when the Disk Usage of the XenServer is over 72%, this will result in upgrade failing on just the XenServer. The SVM will upgrade as expected, but the version of the XenServer will remain at 12.0.0-89