Cache filling up and VMs are suspending


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I've set up an Openfiler VM to configure iSCSI targets. Half way through booting, I've noticed that VM goes in suspend mode. When I try to start VM again, its just suspended without being able to start it. The only thing I can do is force shutdown, however starting it again still persists the same issue. The disks are empty, also have a SSD cache drive.

Any ideas what that could be? I'm a first-timer unRaid user coming from FreeNas so please excuse a newbie.

 

Edit: I think it is due to the cache disk as its all filled up now. I setup a pull schedule every hour, that should solve the issue, I wish it detected cache was running out of disk space and performed the move rather than crashing the VMs.

Edited by The Smith
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If you have a User Share set to Use cache disk: Yes, it will overflow to the array when Unraid sees that cache is too full. Unraid has no way to know how large a file will become when it chooses a disk for it. If a disk has less than Minimum Free remaining, Unraid will choose a different disk. If a disk has more than Minimum Free remaining, Unraid can choose the disk and if it runs out of space you get an error.

 

Minimum Free for cache is in Global Share Settings. You must set Minimum Free to larger than the largest file you expect to write.

 

Each User Share also has a Minimum Free setting which you should set similarly.

 

Also, make sure you understand the difference between cache-yes and cache-prefer. Cache-prefer means you want the files to always be on cache. See this post in the FAQ for more details about the Use cache settings:

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?page=2#comment-537383

 

 

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Thanks for the update. So far, I've tried to clear cache however the cache disk is still full and not clearing up.

I don't have any file shares configured yet, for VMs I selected auto disk creation.

I believe that my VMs that use iSCSI from Openfiler filled up all the cache. In the VM configuration I am not seeing configuration of minimum free. Could you please point me out where would that be configured? Also, I'm wondering why is the cache disk not invoking mover when I manually selected move, I can't seem to have the cache drive cleared.


Thanks!

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2 hours ago, The Smith said:

I don't have any file shares configured yet

Any folder at the top of cache or array disks is automatically a User Share named for the folder. If you look at the Shares you will likely already have some shares.

 

2 hours ago, The Smith said:

I'm wondering why is the cache disk not invoking mover when I manually selected move, I can't seem to have the cache drive cleared.

Only User Shares set to Use cache disk: Yes are moved from cache to the array.

 

Any file at the top level of cache or array disk isn't in a share so won't be touched by mover.

 

With all that in mind, please study my previous post and the link I gave.

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I think the domains share defaults to prefer because that is the expected use for that share. Most people want their VMs to remain on cache for performance. Is anything else filling up your cache? Maybe you need to reconsider how you have things configured. Keeping dockers and VMs on cache for performance, but allowing them to access array storage, is the usual way.

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