quite often not my unraid server fails and no longer access via web or any apps if i shh in i get prompt but reboot and reboot -f fails to do anything 

 

how can i find out why server fails and fix it ?

 

i checked log and lots of errors that i dont know what they mean , i looked as all log is after i restarted 

server-diagnostics-20170930-0748.zip

Edited September 30, 20178 yr by evocraigst

You are correct, logs won't survive a reboot. You can run diagnostics from SSH before rebooting. This will write the current logs to /boot/logs on your flash drive.

You can also set Fix Common Problems to run in "troubleshooting" mode and it will save logs for you.

server crashed again after 12 hours give our take , i log in to ssh takes 2 min to go from  Linux 4.9.30-unRAID. to root@Server:~# ,  after entering diagnostics
 it hangs so will reboot in a min if no response and try freeman idea 

hey @evocraigst just so you know, I am very new at this, and trying to learn. I've had to diagnose so many of my own problems I thought I might be able to help... so my advice should be taken with a truckload of salt.  

 

Looking through your syslog, here is the error that jumped out at me:

 

Sep 30 07:25:58 Server kernel: ata2.00: exception Emask 0x10 SAct 0x0 SErr 0x400000 action 0x6 frozen
Sep 30 07:25:58 Server kernel: ata2.00: irq_stat 0x08000000, interface fatal error
Sep 30 07:25:58 Server kernel: ata2: SError: { Handshk }
Sep 30 07:25:58 Server kernel: ata2.00: failed command: WRITE DMA EXT
Sep 30 07:25:58 Server kernel: ata2.00: cmd 35/00:40:b8:d0:94/00:05:83:00:00/e0 tag 2 dma 688128 out
Sep 30 07:25:58 Server kernel:         res 50/00:00:b8:d0:94/00:00:83:00:00/e0 Emask 0x10 (ATA bus error)

 

This is a disk error with ata2, which is

 

[2:0:0:0]    disk    ATA      WDC WD60EFRX-68L 0A82  /dev/sdc   /dev/sg2 
  state=running queue_depth=1 scsi_level=6 type=0 device_blocked=0 timeout=30

 

So your WD 6TB was throwing up some errors it seems. My first reaction to this is that its a cable problem. Replace the sata cable and then make sure its connected properly. I see that you have 4 of the same WD 6TBs, but I dont know where to find the serial number to see exactly which one it is. If you go into TOOLS and then SYSTEM DEVICES, it will list them out with their serial numbers and you can see exactly which one it is.

I was having the same issues with it crashing awhile back. Was very random. From a few hours to a week. Once it did crash it was unavailable on the network, but you could still use the CLI. Not sure if it was fixed, but it had something to do with the linux kernal they used in the build a few were saying. I updated to the latest beta (6.4 rc7a) and haven't had an issue since. 39 days up no issues.