ConnectionList removeConnection(QueueConnectionImpl connection) {
      if (primary == connection) {
        return new ConnectionList(null, backups, primaryDiscoveryException, primary);
      } else {
        ArrayList<Connection> newBackups = new ArrayList<>(backups);
        newBackups.remove(connection);
        return new ConnectionList(primary, newBackups, primaryDiscoveryException, failedPrimary);
      }
    }
The primaryDiscoveryException flag is stronger than just not having any queue connections It
also means we tried all of the possible queue servers and we'ren't able to connect.
geode-core/src/main/java/org/apache/geode/cache/client/internal/QueueManagerImpl.java