Unable to create a VPS in OpenVZ 7 node using a custom template created in OpenVZ 6: Failed to install the template(s)

Symptoms 

• Unable to start a new OpenVZ VPS using a custom template created in OpenVZ 6. The VPS stays offline in SolusVM

• The following error can be found in the log /var/log/vzctl.log:

  CONFIG_TEXT: Error: Failed to install the template(s): 
  Error: v2-centos-6-x86_64.tar.gz

Cause

Wrong naming for the template.

Resolution

In order to work on OpenVZ 7 a template created in OpenVZ 6 should have the format: {distributive}-{version}-{arch}-{specs}.tar.gz(i.e. centos-6-x86_64-custom.tar.gz) and should be converted to .lz4 format:

1. Connect to OpenVZ 7 node via SSH
2. Rename the template so that the new template has required format:

   # cd /vz/template/cache/
   # cp v2-centos-6-x86_64.tar.gz centos-6-x86_64-v2.tar.gz

3. Convert the template:

   # /usr/libexec/ovz-template-converter centos-6-x86_64-v2.tar.gz