Is it necessary to execute `collator-selection>> set_invulnerables` to make collator eligible to produce blocks?

Question

Our parachain is live now on Kusama. Now some collators want to join the network and produce blocks. However, these collators are not part of chain_spec and invulnerable list.

To add any extra collator to the invulnerable list, we have to perform the below steps:

1. set keys in session via session>>setKeys. They need to have some network native tokens to perform this operation.

2. Share Public key (hex) of their Aura key to Sudo user so that sudo can add collator in the invulnerable list using collator-selection>> set_invulnerables.

Are the above steps mandatory for collator to produce blocks?

Answer 1

You could in collator-selection set desired candidates to a higher number to allow others to post a bond and become collators. If you look at statemine/t for example they currently have as many external collators as invulnerable collators. In order for a new collator to come online this way they must first be part of the current session (i.e. not only does it need to register for the next session but that next session needs to have started before you can register as a collator.).