Maximum numbers of voting members in replica set

Hi All , Can anyone give the reasoning behind maximum number of voting members is 7 only ? Why cant be this 5 or 9 ?

Hello @arpit_k2,

As far as I understand, this is a matter of performance.

The number of voting members could be as large as desired, but the election would take longer for larger numbers, because all of them have to vote.

In essence: too many voting nodes isn’t a good idea.

On the other hand, having 3 voting nodes gives you just one Failover (FO).

What is normally recommended is to choose an odd number of nodes. Every time we pass from even to odd we get an extra FO, but this is not the case for odd to even.

6 voting nodes provide 2 FOs, 5 nodes too. 7 provide 3 fos.

Hopefully someone else will give a more in depth explanation if you need it.