DA10.0 how to search EV8.x and EV10 in concurrently

Rob is correct.  DA will not be able to search two different versions of EV. 

quickest option will be to set up another DA server that can search the EV 8 environment.

Rob is correct in that you can't use DA 10 on EV 10 to search EV 8 indexes.  For DA to work properly, all environments to be searched MUST be on the same EV version.

So, your choices are to use a product or process such as Rob suggested, upgrade your EV 8.x environment to EV 10.x running the same version of EV 10 as your DA server has installed, or stand up a DA 8 server in your EV 8 environment - which also means you'll need to install the DA 8 Client on workstations that your users can use that are different from their normal workstations as you can't install the DA 8 and DA 10 Clients on the same machine.

I'm sorry that we can't run the searches the way you want in your current environment, but the EV binary files (the exe and dll files) used by DA to communicate with EV have to match.

thanks you all for quickly reply.

so ,Rob,can you send me some docs about for how to migrate the data of EV8 to EV10 enviroment

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