[CentOS] A problem with power outages

Sat Mar 24 11:38:02 UTC 2012
William Warren <hescominsoon at emmanuelcomputerconsulting.com>

get a ups that has a usb connection.  What you can do then is when you 
loose power after x amount of time the ups software will gracefully 
shutdown the server automatically.  some ups software will even start 
the server back up once a sufficient charge has been obtained.

On 3/24/2012 7:33 AM, Timothy Murphy wrote:
> I have a CentOS-6.2 server in Italy.
> Every few months the server gets into a strange state
> and stops working after a power outage.
> I should say that this does not occur after every power outage;
> I suspect, but have no real evidence for this,
> that if the power comes back too quickly
> then the machine gets confused because it is in the middle of closing down.
> If I am in Italy the solution is simple;
> I just press the power button on the machine until it stops
> and then switch it on again, and everything works fine.
> I guess that the proper solution is to get a UPS.
> PowerTrust (or Trust) UPS's are available at a reasonable price (€40-€50).
> But I have one question about this solution.
> What if the outage lasts longer than the "life" of the UPS, about 10
> minutes?
> I'd actually like the UPS simply to halt the machine in the proper way
> after say 1 minute; but can this be arranged?
> (If the machine knew it had gone onto UPS,
> this could be arranged fairly simply.)
> There is one other possibility.
> There is a Billion modem/router between the ADSL input and the computer.
> This does not seem to have any problem with power outages.
> So if it were possible to send a message to the router
> which would cause the computer to be turned off and on again,
> that might offer an alternative solution.
> One problem with this is that the Italian ISP
> only offers a dynamic IP address.
> I run ddclient with dyndns on the server to translate this
> into a fixed domain-name.
> But this means that any action of this kind would have to be taken
> before the IP address changes.
> I think it usually stays the same for several days,
> but I guess this might not be true if there is an outage at the ISP's site,
> during a big electric storm.
> Any suggestions, advice or experience of this problem gratefully received.