The right way to do a 301 NGINX redirect without losing backlinks - redirect

Question

I faced an issue with the Google Dec. 2016 update, and lost 99% of my traffic (200K/day to 1K/day). As a result, I've created a new website in the same niche. Now, my goal is to transfer the DA (Domain Authority) to my new domain from the old one. However, while trying to accomplish a 301 redirect such a way
rewrite ^ $scheme://new-domain.com$request_uri permanent;
I faced another issue.
I have a lot of quality backlinks from WSJ, NYT, Wikipedia, etc., which direct to some particular pages on my old domain. If I use such a redirect, these quality backlinks now point out to the empty pages (404).
I have thousands of pages on my old domain, and I can't create so many pages one more time on my new domain.
Here are my primary questions:
1) How can I accomplish a 301 redirect without losing my old quality backlinks?
2) Is there a method to redirect all the old backlinks to my old domain to the main page of my new domain? In other words, I want to redirect all the domain authority from all the old backlinks to the main/index page of my new domain.
I use NGINX.
P.s.:I wasn't able to discover the exact answer to my question on Stack Overflow.

Answer 1

You have a few options, depending on a few things.
Is the old domain hosted on the same server as the new one, with all the old files accessible? If so are you interested in serving those pages still, either from the new domain or the old one, or do you just want all traffic to the old domain to land at the new one?
If its the last option it's easy, you just create two server blocks, one for each domain.
First up the old one, we'll get rid of your rewrite directive as return is more suitable and set up the first block to catch everything to old domain and send it to new domain:
server {
listen 80 default_server;
server_name old-domain.com;
return 301 https://new-domain.com/ # Everything to homepage, or:
return 301 https://new-domain.com$request_uri; # This will include the full request url
}
server {
listen 443 ssl http2;
server_name www.new-domain.com;
...
}
If you still want to serve content from the old domain you can do that too, depends on your aim.