This message is reported after a new connection has started:
ERROR #21 DSI(126 U10PDTE.u10pdte) - (1426) Open server
call to routine 'srv_spawn' failed.
Open Server error: Error: 16115, State: 0, Severity 10
-- 'Could not start thread'.
Explanation
Replication
Server ran out of Open Server threads. srv_spawn allocates
these threads. The maximum number of Open Server threads that a
Replication Server can use is equal to the value specified by the num_threads parameter.
Solution
Increase the number of Open Server threads that the Replication
Server can use by increasing the value of the num_threads parameter.
For example:
configure replication server
set num_threads to '70'