Why does TOS lack resiliance in Power Fail situations?
Posted: 11 Jun 2024, 16:08
Yesterday we suffered a power outage. I have 2 NAS (see Sig) both of which are connected to UPS devices. TOS 5.1 unit lives in an out-building with a large UPS giving 20100 (seconds?) of backup time (according to TOS) and TOS is set to shutdown after 20 minutes without mains power. The second (TOS6.0) unit is lodged in my bedroom using a slightly smaller UPS.
So, when the power failed at 3:30AM I was woken by 2 factors. Firstly the UPS alarrm sounded and then my diabetes 'low glucose' alarm went off - some coincidence! Given the noise possible waking the household and my need to do something "medical", I shut off the UPS at the physical control panel. No harm, no foul but TOS6.0 failed to recover later. That I sort of accept.
Now, as far as TOS5.1 is concerned, the outcome was far from acceptable. When the mains power was restored some 6 hours later, this machine was also crippled and the UPS totally drained. After much head scratching and restoration of the 'correct' FIXED IP addresses (reinstallation of TOS5.1 and configuration)I was confronted with Degraded RAID (Traid) But 3, apparently, good disks. No errors on face value. Because the disks were "good" (presumed), there seemed to be no facility available to repair the raid. Remember, this machine should have shut down after 20 minutes and remained "sane", but obviously something odd happened. (After over 100 days uptime and no concerns.)
Investigation revealed that 2 out of 3 Traid disks had 2 Volume partions albeit with odd sizes showing (roughly 50%). The third disk showed one Volume partition (roughly the correct size for one). [Note: using cfdisk via command line]. I pulled all the disks and confirmed their status on a (Windows) desktop using a 3rd party partition manager tool. My solution was to "guess" that the disk showing single volume was, potentially, the point of failure so I deleted all the partitions on that disk. I was then able, luckily, to successfully, repair the Traid via the control panel.
TOS6.0 remains broken mainly because there is no installation package to rebuild the existing system and it will have to be done from scratch {AGAIN}! Investigation continues.
What I find totally unacceptable in all this is the failure of TOS to shutdown smoothly, conforming to the setting in TOS, while maintaining a coherent raid configuration. I have seen far too many similar incidents (on this forum) of raid failure due to power issues, whether due to 'outside forces' or 'self induced'. Whatever the reason(s) I believe TOS should be much more resilient because we all know these things are going to happen. {Question: ?Developers living in a vacuum where bad, real world events don't happen?}
So, when the power failed at 3:30AM I was woken by 2 factors. Firstly the UPS alarrm sounded and then my diabetes 'low glucose' alarm went off - some coincidence! Given the noise possible waking the household and my need to do something "medical", I shut off the UPS at the physical control panel. No harm, no foul but TOS6.0 failed to recover later. That I sort of accept.
Now, as far as TOS5.1 is concerned, the outcome was far from acceptable. When the mains power was restored some 6 hours later, this machine was also crippled and the UPS totally drained. After much head scratching and restoration of the 'correct' FIXED IP addresses (reinstallation of TOS5.1 and configuration)I was confronted with Degraded RAID (Traid) But 3, apparently, good disks. No errors on face value. Because the disks were "good" (presumed), there seemed to be no facility available to repair the raid. Remember, this machine should have shut down after 20 minutes and remained "sane", but obviously something odd happened. (After over 100 days uptime and no concerns.)
Investigation revealed that 2 out of 3 Traid disks had 2 Volume partions albeit with odd sizes showing (roughly 50%). The third disk showed one Volume partition (roughly the correct size for one). [Note: using cfdisk via command line]. I pulled all the disks and confirmed their status on a (Windows) desktop using a 3rd party partition manager tool. My solution was to "guess" that the disk showing single volume was, potentially, the point of failure so I deleted all the partitions on that disk. I was then able, luckily, to successfully, repair the Traid via the control panel.
TOS6.0 remains broken mainly because there is no installation package to rebuild the existing system and it will have to be done from scratch {AGAIN}! Investigation continues.
What I find totally unacceptable in all this is the failure of TOS to shutdown smoothly, conforming to the setting in TOS, while maintaining a coherent raid configuration. I have seen far too many similar incidents (on this forum) of raid failure due to power issues, whether due to 'outside forces' or 'self induced'. Whatever the reason(s) I believe TOS should be much more resilient because we all know these things are going to happen. {Question: ?Developers living in a vacuum where bad, real world events don't happen?}