I see several things:
Feb 18 21:08:28 DataCore cache_dirs: Arguments=-i Backups -i Media -i Software -i Temp -i appdata -i domains -i isos -i system -l off
Feb 18 21:08:28 DataCore cache_dirs: Max Scan Secs=10, Min Scan Secs=1
Feb 18 21:08:28 DataCore cache_dirs: Scan Type=adaptive
Feb 18 21:08:28 DataCore cache_dirs: Min Scan Depth=4
Feb 18 21:08:28 DataCore cache_dirs: Max Scan Depth=none
Feb 18 21:08:28 DataCore cache_dirs: Use Command='find -noleaf'
Feb 18 21:08:28 DataCore cache_dirs: ---------- Caching Directories ---------------
Feb 18 21:08:28 DataCore cache_dirs: Backups
Feb 18 21:08:28 DataCore cache_dirs: Media
Feb 18 21:08:28 DataCore cache_dirs: Software
Feb 18 21:08:28 DataCore cache_dirs: Temp
Feb 18 21:08:28 DataCore cache_dirs: appdata
Feb 18 21:08:28 DataCore cache_dirs: domains
Feb 18 21:08:28 DataCore cache_dirs: isos
Feb 18 21:08:28 DataCore cache_dirs: system
Feb 18 21:08:28 DataCore cache_dirs: ----------------------------------------------
Don't cache appdata, domains, isos, or system. It doesn't help on those shares. I assume you have them on a SSD cache or Pool device. For the moment, I'd remove the cache dirs plugin.
Also remove S3 sleep and preclear plugins for now.
There's nothing wrong with these plugins, I just want to limit the number of things that could get in the way.
I also see these, but I don't know if this is an issue or not:
Feb 18 21:09:03 DataCore root: Starting Nginx server daemon...
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.974 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *15 limiting requests, excess: 20.974 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *15 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *13 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *15 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *13 limiting requests, excess: 20.973 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.972 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *60 limiting requests, excess: 20.972 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *15 limiting requests, excess: 20.972 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *13 limiting requests, excess: 20.972 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.971 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *59 limiting requests, excess: 20.971 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *14 limiting requests, excess: 20.971 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *60 limiting requests, excess: 20.971 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *15 limiting requests, excess: 20.969 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *13 limiting requests, excess: 20.969 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *61 limiting requests, excess: 20.969 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *59 limiting requests, excess: 20.969 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *14 limiting requests, excess: 20.968 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:03 DataCore nginx: 2022/02/18 21:09:03 [error] 9771#9771: *60 limiting requests, excess: 20.966 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:08 DataCore nginx: 2022/02/18 21:09:08 [error] 9771#9771: *15 limiting requests, excess: 20.384 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
Feb 18 21:09:08 DataCore nginx: 2022/02/18 21:09:08 [error] 9771#9771: *61 limiting requests, excess: 20.383 by zone "authlimit", client: 192.168.178.140, server: , request: "GET /login HTTP/1.1", host: "192.168.178.21", referrer: "http://192.168.178.21/Main"
You said this is a disk mounted with UD. Can you give a screen shot of the UD page? Also, how are you doing your copying?