5.18 Moving a User Domain to a Different Database Server

User domains can move to different database servers.

The target Oracle Exadata Database Server must meet the following requirements:

• The target database server must have the same Oracle Exadata System Software release installed with Oracle VM.

• The target database server must have the same network visibility.

• The target database server must have access to the same Oracle Exadata Storage Servers.

• The target database server must have sufficient free resources (CPU, memory, and local disk storage) to operate the user domain.

  • It is possible to over-commit virtual CPUs such that the total number of virtual CPUs assigned to all domains exceeds the number of physical CPUs on the system. Over-committing CPUs can be done only when the competing workloads for over-subscribed resources are well understood and the concurrent demand does not exceed physical capacity.

  • It is not possible to over-commit memory.

  • Copying disk images to the target database server may increase space allocation of the disk image files because the copied files are no longer able to benefit from the disk space savings gained by using OCFS2 reflinks.

• The user domain name must not be already in use on the target database server.

The following procedure moves a user domain to a new database server in the same Oracle Exadata System Software configuration. All steps in this procedure are performed in the management domain.

1. Shut down the user domain.

   # xm shutdown DomainName -w
   

2. Copy the user domain disk image and configuration files to the target database server.

   In the following examples, replace DomainName with the name of the domain.

   # scp -r /EXAVMIMAGES/GuestImages/DomainName/ target:/EXAVMIMAGES/GuestImages
   

3. Obtain the UUID of the user domain.

   # grep ^uuid /EXAVMIMAGES/GuestImages/DomainName/vm.cfg
   

   An example of the user domain UUID is 49ffddce4efe43f5910d0c61c87bba58.

4. Using the UUID of the user domain, copy the user domain symbolic links from /OVS/Repositories to the target database server.

   # tar cpvf - /OVS/Repositories/UUID/ | ssh target_db_server "tar xpvf - -C /"
   

5. Start the user domain on the target database server.

   # xm create /EXAVMIMAGES/GuestImages/DomainName/xm.cfg