Can you recommend a disaster recovery automation tool?

Arpio is an excellent tool for DR Orchestration for AWS-based solutions. See Arpio.io.

We use a combination of Veeam for Hyper-V Hosts and VMs and Zerto for VMware VMs. Everything is on-site except for Exchange which was moved to the cloud when we upgraded to M365 with a backup also in the cloud.

For automation, both Zerto and Veeam work with minor help and can be integrated with scripts to help the process.

The benefit is they can be tested on a regular basis in a sandbox area to make sure the backups in the DR site are valid without interrupting current backups or production. Complete Failover accomplished within an hour with data loss of 15 minutes. (Careful, as the fail back to production takes much longer, estimated 8 hours! Unless you prepare a second failover on the production side then you are back to only an hour with minor interruption of data loss during the moving process.)

Veeam and Commvault have very good tools for DRP automation.

Vmware SRM with VCF or Cloud7. 

Here is a user endorsement for 
Quorum Backup & Recovery

• Simply put, this software does exactly what is designed to do. It delivers a backup and disaster recovery platform that works flawlessly. It is a turnkey solution that provides local and remote backup, file recovery, DR and archive that is managed in one, very easy to use interface. Configuration of the platform is a breeze. I have been using this platform for almost 10 years and it has never failed to do its job. Everyone at Quorum is super easy to work with from the account managers to the implementation team and the technical support staff. They were very thorough with pre-purchase discovery, making sure we got exactly what we needed. There was a lot of pre-deployment discussion concerning our environment and they were on top of every aspect of the initial deployment, even dispatching an onsite technician to assist. Any time we have had a technical or configuration issue, Quorum's tech support team is extremely responsive and they stick with the issue until it is resolved. I am running the platform on its own on-prem hardware that Quorum provided and preconfigured. This is in contrast to solutions I have used in the past that required me to provide hardware and configuration
  
  

It depends what you mean by 'Automation'. We use a backup product that does all the usual stuff (incremental backup to the cloud on a schedule, holds local copies, encryption blah blah etc. etc.). If you know what you are doing you can build yourself a recovery appliance that holds the latest backup as a stand-by image in a ready-to-start form. Every time the system detects a fresh backup increment, the stand-by increments to match, so you always have the latest backup of your system one click away from starting up. What's neat is that you can have this recovery appliance on or off the target site - or both, or as many locations as you want. We normally have the recovery appliance on the client's site (in a different part of the building) and also keep a copy on an appliance here in our machine room. It's so easy to do that I test-boot the latest stand-by images (for most of our clients) on a weekly basis just to validate the process. (A backup is only as good as your last validation...) And it can all be managed remotely!

Are you talking about virtualized machines or physical machines? If they are virtualized, on which platform they are virtualized? VMware or HyperV?

For VMware platform I can recommend vSphere Replication & SRM.

What backup software are you using ? Both Veeam & Druva comes with DR orchestration