3

There are trade-offs regarding data safety vs performance when configuring storage. Some faster settings are only recommended when one does not expect power outages, e.g. because the server has a battery backup unit (BBU).

Manuals and articles always mention loss of power as a source of danger. Since we do have the equivalent of a BBU (CacheVault) in the server and a UPS in the server room, we don't expect literal power loss.

However, does all the advice regarding power loss also apply to pressing the physical reset button of the server, e.g. when it becomes unresponsive? Does the reset button cut the power directly in such a way that it could lead to data corruption, even though there is a CacheVault in there?

The server uses a Supermicro SMC2208 RAID controller with RAID6 and ext4 filesystem.

In summary, my main question is whether I should treat hard resets (pressing the reset button) as the equivalent of power loss for my purposes.

The server does get unresponsive about once or twice a year and since we don't have a keyboard attached to perform Alt+SysRq+REISUB, it is more convenient to just press reset. I wonder if this practice is very problematic and risky in our setup.

2
  • Use your IPMI remote console. Jan 31, 2019 at 13:18
  • 2
    Hard reset has the same impact as power failure. But I'd better troubleshoot, why your server gets unresponsible. Jan 31, 2019 at 15:07

1 Answer 1

3

"The server does get unresponsive about once or twice a year and since we don't have a keyboard attached to perform Alt+SysRq+REISUB, it is more convenient to just press reset. I wonder if this practice is very problematic and risky in our setup."

I would suggest yes, though the risk might be quite small, it's non-zero. If a device is truly unresponsive this is a moot point of course, but if you're concerned about data loss you should always choose the most orderly shutdown path available to you.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.