Let me start by apologizing since I know this question is going to be obvious to plenty of people on here.  But thankfully, I have UNRAID to thank for either my laziness or my inability to know the answer to this question.  UNRAID has just worked for me for so long that I not only don't have to think about it, but end up forgetting everything I did to set it up.  So, thank you UNRAID for giving me one less thing to think about in my life.  

 

I have a simple setup with a six drive array and one 500 GB cache drive.  The cache drive has about six dockers on it and that is about all I use it for.  I did tinker with VMs at one time, but don't use them.  It only uses about 70 GBs of space.  The cache drive is 5 years old now and I'm starting to get nervous it might fail.  Early on this wasn't a big deal since I could easily setup everything again.  Now, it would take more work than I would like to admit (refer to laziness above).

 

I did try to do some research in this space to see if an obvious answer exists, but was met with more things that I didn't understand because UNRAID has continued to advance even though I haven't.  Ultimately, my question is, what would be the easiest way to safeguard against my cache drive failing?  Is it possible to write an image of it onto the array?  Is there something that possibly automates this every day / week?  Is maybe the only solution to run duplicate cache drives?  Again, when it comes to "easiest" I suspect there is an obvious answer here, but I'm not sure what it is.  Any help is appreciated.  Thanks.    

I would suggest you checkout the appdata backup plugin. It will backup most of the default data usually kept on cache.