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- Fixed clients intermittently failing to connect to a Distributed Authority session when the host took more than a few seconds to publish the session's join code. The join now keeps waiting for the full timeout instead of giving up after roughly ten seconds. - Joining a Distributed Authority session no longer fails with a `NullReferenceException` or a JSON parsing error when the session metadata on the lobby is temporarily missing, empty, or malformed. These states are now treated as "the join code has not been published yet" and the join keeps waiting, failing with a `SessionException` if the timeout is reached.
Based on Forum-Issue-1717323 with a continued internal discussion here.
Description
I’m seeing an intermittent failure when starting a Distributed Authority session with Unity Services Multiplayer + NGO + UTP + Relay.
To debug it, I embedded the com.unity.services.multiplayer package locally so I could add instrumentation inside the package and also added a few traces in com.unity.netcode.gameobjects / Unity Transport. That let me compare a good run and a bad run at a fairly low level.
What happens in the good case:
What happens in the bad case:
A few notes from instrumentation:
So the failure appears to be:
It looks more like “relay established, but the connection is never accepted/approved”.
Has anyone seen this before, or does this pattern point to a known issue in the Distributed Authority/Relay/NGO handshake path? In particular, is there a known reason why a client would reach Relay Established but never receive Accepted, eventually failing with MaxConnectionAttempts?
Initial setup
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Reproduction steps
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Expected behaviour
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Actual behavior
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Logs and Links
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