The bug was fixed in Plesk Obsidian Preview (8 May 2019), https://docs.plesk.com/release-notes/onyx/change-log/#179-preview14.

[+] It is now possible to select which NS record will be set as a primary name server in the Plesk interface. It can be done using SOA record, for DNS Template - SOA record template.

Thank you all for comments and voting!

The thread about this bug on our forum is https://talk.plesk.com/threads/dns-order-of-records-unreliable-and-thus-primary-master-name-server-in-soa-broken.347522/

This voting system is silly for stuff that is done plain wrong.
It's not a "feature".
I like Plesk a lot but it contains several bugs that take years to get fixed even if they are properly described.

Suggesting that people should "vote for it" is cheeky and insulting.
If things are plain wrong and only 1 person notices it, it should take precedence over some feature that gets 1000 votes.

Same here, @Plesk Staff. This is STANDARD in using DNS servers..please include that YESTERDAY!

Yes please!

It would be really nice if we would be able to select one of the NS records in the zone on the SOA tab to be the primary. Instead of a random pick.

It would be nice to set explicit the Master and ***** DNS Servers for a Zone or Template. I known First entry in Database is used as Master but explicit Setting would be better.

discovered and reported this so long ago that I almost forgot about it.
Why this still isn't fixed.
It' even changes sometimes.
I noticed this after I created a script that compared the SOA record with the IP of the authorative server to check for orphaned domein names.

This must be solved asap, We need to have control over this.

Can someone of the developer please take care of this problem we all have here, it's quite not very difficult to add a database entry and a button to define a ns-record as primary.

Thanx, have a nice weekend and please start on monday to think about a solution :-)

I was surprised when I saw my secondary slave dns was acting as primary dns!!!
It´s very important to have absolute control over this.
Please add this feature as soon as possible. Thanks.

Need this. As i set the secondary NS entry first this is now listed as primary (what i do not want) and until now didn't find a way to change this.

Hello, I like also this features. Is better that plesk, add, into dns soa setting, an simple tab with "primary ns" so, when the DNS zone is generated, the primary NS is the NS that the admin (or the user) have set into dns template.

Imagine a situation like this. 4 NS Entries on different hosts: http://imgur.com/ahkNZ2Q
I added the NS Entries in the order I labeled them.

Because I added ns.xxxxx.com first, it will be the primary NS. If I want to add a new primary NS then I have to delete all existing NS Entries, add the one I want to be the new primary NS and then re-add all the other NS Entries.
That's fine, as long as you know Plesk behaves this way. It's not a big deal – how often do you change your primary NS? The problem is, that this is not documented. The only way to check which one is listed as primary is with nslookup. Theres no way to see what acts as primary NS with Plesk.

My first thought was that this should be selectable in the SOA Records.

I bet that many users don't even notice that some (secondary) Slave Nameserver is their primary Nameserver. The only thing you notice is that there's a delay of adding subdomains and being able to access them.