No, this is unexpected. But your description is very vague so it's impossible to know what the problem is. Can you describe it in more detail? Can you share logs or other error messages? Which version of OpenJDK 8 are you using? If shards are unassigned then can you use the allocation explain API to find out why?
Thank you.
Below are the details
openjdk version "1.8.0_181"
OpenJDK Runtime Environment (build 1.8.0_181-b13)
OpenJDK 64-Bit Server VM (build 25.181-b13, mixed mode)
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