Accepting connections, yes, but for a client that is dependent on being able to establish ssh connections that is not enough. They would want to be notified on the ability to make successful connections.
Keep in mind that this is only a problem in special situations, almost no regular Linux servers carry any services that care about being able to establish ssh connections, that cannot reconnect and use appropriate socket options. For other services than ssh, such as databases, this is much more common. And for those, it is not enough that the server has opened a listening socket.
When building distributed systems, this is something you need to think about. Not so such with local systems. But the same principles apply. And the only robust way is to poll for readiness. Signalling readiness is both complex, when the dependency chains are non-trivial, and prone to error, when readiness signals arrive out of order or are dropped or fail for some reason. This could be because of operations failure but make for hard to debug cases. Dependency chains that mysteriously stop because of permission problems with out of band traffic is both classic and unnecessary problem.
All of this complexity go away when polling. This is why you should adopt this design in the somewhat unlikely case you have clients that depend on being able to make ssh connections.
Keep in mind that this is only a problem in special situations, almost no regular Linux servers carry any services that care about being able to establish ssh connections, that cannot reconnect and use appropriate socket options. For other services than ssh, such as databases, this is much more common. And for those, it is not enough that the server has opened a listening socket.
When building distributed systems, this is something you need to think about. Not so such with local systems. But the same principles apply. And the only robust way is to poll for readiness. Signalling readiness is both complex, when the dependency chains are non-trivial, and prone to error, when readiness signals arrive out of order or are dropped or fail for some reason. This could be because of operations failure but make for hard to debug cases. Dependency chains that mysteriously stop because of permission problems with out of band traffic is both classic and unnecessary problem.
All of this complexity go away when polling. This is why you should adopt this design in the somewhat unlikely case you have clients that depend on being able to make ssh connections.