Docker application PlexMediaServer has volumes being passed that are mounted by Unassigned Devices, but they are not mounted with the slave option

So I have a question what does the Slave option do ? 

I am using an SSD for plex and the slave option doesn't seem to start the drive before the docker ? which I would have thought it would do.

So what is that option for  ?

31 minutes ago, jschultz070 said:

So I have a question what does the Slave option do ? 

It allows docker containers to see paths mounted after Docker starts. Without R/W Slave mode set, the container only sees paths mounted before Docker starts.

ok thanks for that. I thought the OS would make sure that drive or path would be mounted before the docker started.

Thanks for the clarification. 

1 hour ago, jschultz070 said:

ok thanks for that. I thought the OS would make sure that drive or path would be mounted before the docker started.

Thanks for the clarification. 

Further clarification. It is not about whether the drive is mounted before "the docker" starts. It is about whether or not the drive is mounted before the docker service starts. If the drive isn't mounted when the docker service starts (basically at array startup), then the slave option is needed.

I am having this same issue. I cant mange to find the option to turn on rw slave for the appdata config path for the plex docker template. unsure what I'm missing. 

thanks.

Edit button on the Path then select the Access mode 

As an aside, this test is going to be removed from FCP as I don't believe that it's strictly necessary anymore except for some very specific use cases, and in certain cases actually has the opposite effect

So if I haven't had any problems so far (I've been running my Plex server for about 2 years now) I shouldn't change the R/W Slave mode option as FCP suggests?