What alias information moves over during a sync with the 9.X branch of the product?
With the 9.X branch of the Ektron product, auto-aliases are regenerated during the sync process. This may cause temporary 404 responses on web pages. As such, it's recommended to set up a web site caching strategy, or to sync during 'off-hours' to negate this known behavior.
While the auto-aliases are regenerated, their aliasing rules are physically synced over. If you see an issue with auto aliases not pulling up after a sync, ensure that you have upgraded to address known auto aliasing issues and verify the rules are set up correctly within the workarea in the receiving site. These aliasing rules are under Settings>Configuration>URL Aliasing>Auto Aliases.
You can also 'Edit' the aliasing rule to see if that will force the regeneration process.
These types of aliases are synced over using the traditional sync methods by use of tracking tables in the databases. If these do not pull up on the receiving side, there may have been an issue with the tracking tables. We recommend to reach out to Support if it is felt that is the case for further analysis of the problem.