Download the zip file for the Linux-based SRM offering. Extract the files to a local folder. Navigate to the admin page of the SRM server with your chosen web browser. The web address is https://<srm server>:5480. The default user is admin with a password you selected upon deployment of SRM.
Click on the left-hand side panel listing for Storage Replication Adapters.
Click on the New Adapter button that appears on the right of the panel.
Click Upload and navigate to the extracted folder of the downloaded SRA. Choose the .tar file. If you only see a .exe file, you downloaded the Windows version, not the Linux release. Re-download the correct SRA if so.
Select the tar file and click Upload.
Once the process completes, the SRA will properly report in SRM:
Repeat this process on both Site Recovery Manager servers. Ensure that the exact same SRA version is installed on both SRM servers as well.