Hi,
my advise:
first check the requirements for SAS 9.4 (check foundation and all your SAS solutions and products, including the SAS/ACCESS Interfaces to your datasources) on the OS you want to use: http://support.sas.com/resources/sysreq/
Added to the comment frim SASWiki: you can find different kind of migrations for SAS:
data migration (Databases or sas datasets)
Applications and programs from users
Move your server from one domain to other, change your server name/ips/other basic configurations
SAS software to newer versions: in this case, you can do an upgrade of the software, or install the new software from scratch and then migrate the metadata and the content.
For the first one, check: t if you move from a 32 bit to 64 bit environment and software ( I am expecting you are already on 64) and if you are changing your OS. If so, you will need data migration
The second one will require an analysis more in detail that I cannot describe now and here.
The third can be supported by cloning the (vm) servers, the hostname update utility, changing configuration files, etc
And the forth can be approached as commented and then decide if you will export/import metadata and BI content or you will use the SMU (SAS Migration Utility) to migrate to the new version. Or upgrade the software and then fix what is required, but it is risky, sometimes you don;t need to do anything else and it is easy, but sometimes .... better not to explain.
My advise: read some public and official documentation that will help you a lot:
http://support.sas.com/rnd/migration/utility/upgrade.html
http://support.sas.com/kb/50/282.html
http://bi-notes.com/2013/11/sas-administration-migration-users-groups-roles/
http://support.sas.com/documentation/cdl/en/bimig/63853/HTML/default/viewer.htm#n01023intelplatform0...
Hope this can help you