I've now tried with a couple of different disks, even formatted the smaller (600GB) one to Ext4 but still the same problem. Also tried plugging into the USB 2 port rather than the USB 3 - no difference.
Looks like I'll be sticking with the RPi3 setup.
Just tried the other suggestion and replaced the SSD with a MicroSD loaded with the latest nightly. Unfortunately the same problem occurs.
I read more about the cache and followed the links and as far as I can see this refers to video playback cache only not things like changing file names or adding new videos on.
I can do a reboot every time I make a change but I'm baffled why no one else seems to be experiencing this problem. Maybe nobody has their drive connected to the Pi directly and access over LAN or something.
<memorysize>0</memorysize> Just click the link and read...
Sorry about misremembering your post.
However, I don't want to keep the whole SAMBA cache in ram I want it on disk where (I think) it belongs.
The link does give some interesting options which I can try. I'm not 100% certain exactly what some of them will do so it will be a bit more experimentation.
Thanks for the link.
I'm not sure whether this is something for LibreElec or Kodi. If Kodi please let me know and I'll post over there.
I've now tried SAMBA and FileZilla for transferring files to the RPi4 and SAMBA to rename files on the RPi4. I've tried turning my PC off after the transfer to make sure the share is disconnected. I've tried logging in to the RPi4 via SSH and running sync. I've tried waiting a while, about 10-15 minutes and overnight, just to see if the disk would get updated and the answer in all cases is no - it doesn't.
Rebooting, or powering off through the menu does flush things down to disk but its a bit of a pain to have to do this (and remember to have to do this) after any alteration, or addition to the disk.
I can appreciate, as Da Flex, posted that not writing down was to help prolong the life of MicroSD cards but could a switch be added to allow it to happen?
The reason I'm wondering if this is a Kodi issue is that if I change skin this is also not stored (or from my simple test) unless the Pi is rebooted.
The results so far are that sync doesn't work. I tried altering a couple of file names, ssh into the RPi and ran sync, ran the watch to show status - no dirty bits, turned off, turned on - Kodi will not access the disk.
The good news is that reboot or power off do seem to flush things to disk.
Didn't you try the sync command before unplugging the USB storage?
See for instance this webpage: https://www.kaper.com/notes/linux-sy…or-copy-to-usb/
Not yet. I've just been experimenting to see what was causing the corruption. If running sync works it will be good but a bit inconvenient since I'll have to ssh into the Raspberry Pi to run it. I need to run a few other experiments and have a look through the addons yet.
You could add a timeout to your poweroff / reboot. Maybe that's needed to complete buffer writings.
After some experimentation I think this is (sort of) the problem. I renamed a file, left it about 10 minutes then pulled the plug - corruption occurred. I think its the proper reboot/power off that's needed.
Can anyone on the team let me know how frequently buffers would be flushed to disk or if its only on reboot / power off.
Went into a charity shop this afternoon and bought a 2nd hand TV so I can now set up the Pi4 and mess around. Just updating my backup 6TB HDD so I can add that on. About the only thing different will be the fact I don't have a spare Haupage tuner. I do have a single tuner so I'll add that in to copy the setup I have problems with.
As is usual with computers just sit back and watch everything work perfectly!
Worth a try, after switching to microSD card
Yup - still NTFS.
I have thought of swapping to an SD card since that is one of the significant differences between the two setups, and one I'm willing to alter - no way am I replacing the nice stable s/w on the Pi3s. I'm recording the Rugby World Cup happening in NZ for a friend so I have time to buy an SD card from good old Amazon.
I'll report back after the rugby.
Thanks for trying to help. I realise I should have posted the configuration as I did in the earlier posts about this. Its a 4GB RPI4 with a 120GB SSD or LibreElec & Kodi with a self powered 6TB HDD for films, both plugged into USB 3 ports, dongle for USB mini keyboard plugged into a USB 3 port on the 6TB HDD& Haupage dual tuner plugged into USB 2 port with TVHeadend. Connected via powerline ethernet to a mixed Windows (3 laptops, 1 desktop all on powerline) & Linux (1 laptop using wifi) LAN. I transfer stuff to the 6TB HDD via SAMBA.
The RPi3 setup had two RPi3s both running off microSD cards, one with the Haupage tuner and the other HDMI to the TV, both plugged into powerline.
With the RPi3 setup, started back in 2018, I have not experienced corruption, with the RPi4 setup I don't think it even managed a week without corruption.
Basically I'm still trying to understand why so I can stop it happening and start using the RPi4.
I was talking about A/V streaming buffer, because you didn't mentioned a specific buffer. Kodi's default setting includes Samba caching into RAM. Maybe you have to increase the "memorysize" parameter to keep the whole Samba cache in RAM.
I was just asking about any buffer that might need flushing to an external USB drive. Something causes LibreElec/Kodi/RPi4 to corrupt an attached 6TB HDD. This does not happen with the RPi3 and its older s/w. What I need is to identify why so that I have a chance of stopping it happening and I can switch over to the RPi4.
So back to the question - does LibreElec/Kodi/RPi4 flush any outstanding buffers to an external USB HDD before rebooting or powering off?
Does that include access over SAMBA, just writes to its databases or what?
I've had corruption on my 6TB HDD again. I had been looking at different skins and I had rebooted / powered off the Pi a few times and I had made changes to the data on the HDD so my latest wondering is does LibreElec flush the buffers to a USB connected drive and wait for that to complete before either rebooting or powering off?
So far I've managed at best a week without corruption so for that and an issue with playing back recordings from TVHeadend I've sent the Pi on sabbatical for a few months.
Thanks to those who've helped me so far and as Arnie says "I'll be back" 
Yes, your diagram is what I meant by that option.
Unfortunately, you seem to have conflicting requirements. You cannot have an isolated system with the two Pis and connect to one of them from outside of that system. Just can't be done.
Its worth going back and looking at what you're trying to achieve. A few questions
1. why do you want the separate file server, what is its purpose?
2. why not connect the SSD directly to RP2 which WILL give you the maximum speed connection?
3. what speed is actually needed to stream 4k60Hz iso files (someone else might be able to answer this because I can't)?
Its an interesting approach, but unless you are planning to add more nodes in I'm not to sure what you're trying to achieve. Why not just plug the SSD straight into RP2?
I have no idea if this will work (mainly because I've not tried it) but two thoughts did occur 1) enable wifi on RP1 and use that to connect to the router or 2) pop a mini hub in, plug into RP1 and make the other connections through that that would allow the router to be part of the setup.
Thanks for the info. I loaded the 16/9/22 nightly (I was on the 4/9/22 I think before) so that I included the latest update to SAMBA and am pretty much back to where I was before I started the upgrade ..... I think <VBG>
I'm bending my brain trying to understand the Amber skin enough to make a small mod so I won't be upgrading for a while, in fact if the 16/9/22 version works I may just wait until the release version.
