Hoopster

Often, flash devices that show as incompatible in the Flash Creator can be successfully used with the manual installation method.

No, not normal.  My 8TB parity takes a little over 16 hours to build.  A reasonable rough estimate is about 2 hours per TB.  Your 12TB parity should rebuild in approximately 24 hours if everythng with your server is as it should be.  Clearly, there are some problems.
 
You can use your server during rebuild altough that can slow down the rebuild depending on how heavy the use.  You should minimize the use.  Another option is to use the Parity Check Tuning plugin and spread a parity build over several low-use periods such as at night.  I typically do my rebuild in two roughly 8-hour (midnight to 8am) sessions.

They probably have blank variables, which, up until version 6.12.8 of Unraid, was not a problem.  This happened to me as well.  A docker container disappeared and could not be added again even through Previous Apps.
 
You likely need to install the Docker Patch 6.12.8 plugin which will fix this and let docker containers with blank variables be installed.  You can then decide if you need to fill in these variables.  This, of course, assumes you are running version 6.12.8 of Unraid.

I don't know what 5G service you are planning to use in your home, but, the T-Mobile 5G gateway, for example, has an Ethernet port to which a switch or router can be connected.  A lot of third-party routers have 4-port switches built in.  In either case, it should be possible to connect your Unraid server to an Ethernet port if you go with a 5G Internet service that has a gateway with an Ethernet port.
 

No, shutting down does not trigger the Mover.  Mover can be run manually before shutdown if you wish, and, of course, the schedule can be changed to any time you wish.  3:40am is just the default. 
 
How long mover takes depends on how much data needs to be moved from cache to the array.  You can control by user share if it writes data first to cache (moved to array by Mover) of if it writes directly to the array.  I don't have any shares currently writing first to cache so the Mover is not an issue in my case.

You have export in share security settings set to No.  This hides the share from Windows.  You need to set it to public or another setting with secure access if you want a share visible in Windows.

It does a lot more than that.
https://unraid.net/connect
 
Have you provisioned a myunraid.net certificate?  https://docs.unraid.net/connect/help/#manage-your-server-from-within-the-connect-ui

In the settings for the drive in Unassigned Devices, did you enable sharing?
 

You have macvlan call traces.  Try switching the docker network type to ipvlan.  Settings --> Docker --> docker custom network type
 
Prior to Unraid 6.12.x (don't know what version you are running since you did not include full diagnostics) usually macvlan issues only occurred on systems where custom IP addresses were assigned on br0.  Now, (6.12.0+ as mentioned in the release notes) with some hardware, macvlan problems can appear even without custom docker container IP addresses.
 
 

Did you read this section in the 6.12.0 release notes (specifically the last paragraph)?
 
Network Improvements
 
We added a new section under Settings->Network Settings->Interface Extra, allowing users to define which interfaces the Unraid services use. By default, all standard interfaces with an IP address are included in the list of listening interfaces.
 
The tunnels of the built-in WireGuard function of Unraid are automatically added or removed from the list when the Wireguard tunnels are activated or deactivated. The user may exclude these tunnels from the list of listening interfaces.
 
To use the Tailscale or Zerotier interface, it is required to add the interface name or IP address of the communication to the list of included listening interfaces.
Important: It is imperative that Tailscale or Zerotier container is running before the interface is added to the list.
 
 

You probably have a custom IP address assigned to one or more docker containers which are causing your crashes.

Did you read the 6.12.0 release notes which explains what you need to do to get Tailscale to work with 6.12.0?  The applicable section is called Network Improvements.

@grumpy When you upgrade within the GUI (Tools -->> Update OS) a folder named previous is created on the root of the flash drive.  This contains the files associated with the previous version of Unraid that was installed on the flash drive. After my failed upgrade to 6.12.0 (would not boot at all), I just copied all of the files in the previous folder back to the root of the flash drive (overwriting everything) and I was back to 6.11.5.

Mover only moves data off of cache disk and onto the array for shares that are set to cache: yes
 
You need to read and understand the various cache settings and make sure you have the shares set properly
 
Cache settings documentation.
 
 
This is the expected behavior.  This does not move anything off cache drive that is already there.

When you setup appdata in a different cache/pool drive location, simply reinstall all your previous docker containers from the Previous Apps section of the Apps tabs.  They will be restored with all previous settings intact.
 
If your data is to be moved to different drives, you can use the Unbalance plugin to move the data where you wish.  If it is staying on the same drive(s) you can preserve certain disk assignments in a new configuration.  Data remains intact.  You can also reassign drives to new slots if you wish and data remains intact as long as you do not format the drives.

Some additional featuers (such as reflink) were added to XFS a while ago that results in more space being used when initializing the filesystem with a format.  55G for an 8TB drive is not unusual.

According to this chart at least a 1050 is required for 4K to 1080p transcoding (select 4k to 1080p in dropdown).  Your 750 Ti won't cut it so it falls back to CPU.

/mnt/user is the view of the data via user shares (/mnt/user/photos, /mnt/users/movies, etc. depending on what user shares you may have defined)  User shares can span disks if you have set them up that way.  /mnt/user0 is the view of the user shares minus whatever may exist on cache pools.
 
/mnt/diskX are disk shares and one exists for each physical disk.

Coursera has some good basic networking courses.  There is also Khan Academy, Udemy or just YouTube channels.  Just Google what you are looking for.  You'll find a lot of options.  Some may have a cost, others are free.

These do not exist unless you setup the syslog server.
 
Like the Unraid OS, the syslog is in RAM.  A reboot wipes it out which is why anything logged before a reboot is gone unless you have the syslog server running which records it all elsewhere.

The shrink array process is designed for this.

Settings --> Network Settings and set DNS servers for eth0 (the interface Unraid uses).
 

No
 
No
 
New Config lets you reset disk assignments in the array.  It will have no impact on preclear status, license, plugin or docker configuration.

I have one of these flashed to IT mode and it works great in my Unraid server. 
 
Yes, that should mean it is in IT mode.  The PERC H310 is an LSI 9211-8i clone and is normally a RAID controller but IT firmware turns it into an HBA card.