11–20 of 71 posts
Interesting, thanks for posting! Could you talk quickly about why it's interesting to predict drive failure? Is it to understand how many replacement drives you might need to order in the short term, or is there value beyond stock management of drives?
Interesting, thanks for posting! Could you talk quickly about why it's interesting to predict drive failure? Is it to understand how many replacement drives you might need to order in the short term, or is there value beyond stock management of drives?
This data should be put into smartmontools or a separate tool to give a simple good/bad rating as the actual values are somewhat meaningless w/o data.
Would you enable an option for smartmontools that sent all your drive SMART data to a cloud hosted db (with as little identifying information as possible) and tell it when you had a drive fail - in return for that same service alerting you with "best estimates" of your risks of drive failure?
#!/bin/bash
smartctl -a /dev/sda > /root/smartStates
grep Reallocated_Sector_Ct /root/smartStates > /root/stats
grep Current_Pending_Sector /root/smartStates >> /root/stats
grep Offline_Uncorrectable /root/smartStates >> /root/stats
grep UDMA_CRC_Error_Count /root/smartStates >> /root/stats
touch /root/statsOld
cmp /root/stats /root/statsOld
result=$?
if [[ $result -ne "1" && $result -ne "0" ]]
then
echo "Something went wrong"
exit -1
fi
if [[ $result -eq "1" ]]
then
echo "Files are different\n"
cat /root/stats
fi
mv /root/stats /root/statsOld
rm /root/smartStatesInteresting, thanks for posting! Could you talk quickly about why it's interesting to predict drive failure? Is it to understand how many replacement drives you might need to order in the short term, or is there value beyond stock management of drives?
In a non-RAID context, for example NoSQL databases that keep 3 copies of chunks of data, knowing about a failure in advance means that you can abandon using that drive slowly, without it becoming an emergency.
Interesting, thanks for posting! Could you talk quickly about why it's interesting to predict drive failure? Is it to understand how many replacement drives you might need to order in the short term, or is there value beyond stock management of drives?
Not OP, but: Perfect predictability would obviously be beneficial, in that you could get by without any redundancy. But even imperfect predicability can help you reduce the required number of drives for a set level of security.
Such nuisance for what might be a good read.
Ten years ago when I was I trying to learn how to "program", I wrote this bash script (to be added into /etc/cron.daily) that dumps a few smart stats that are normally 0 or slow changing, diffs it with the copy from the previous run, and if anything is different (and cron in configured right) it will email you the diff. Every linux machine I touch gets this file dropped onto it. I've replaced many hard drives because…
Earlier quoted context omitted.
In a non-RAID context, for example NoSQL databases that keep 3 copies of chunks of data, knowing about a failure in advance means that you can abandon using that drive slowly, without it becoming an emergency.
If you have three replicas, who cares if one fails? Just wait for it to fail and rereplicate from the survivors.
Earlier quoted context omitted.
Not OP, but: Perfect predictability would obviously be beneficial, in that you could get by without any redundancy. But even imperfect predicability can help you reduce the required number of drives for a set level of security.
Yeah but no. The problem is that absence of smart counters does in no way indicate good health of the device.
Not perfectly, obviously, but this is about probabilities.
Say you want some level of data security (i. e. 99.9% over one year).
The formula for the risk of data loss is (r^n) where r is the failure rate of drives and n is the number of drives (assuming independence and using just mirroring).
But – if you have a test that can predict failure with some probability s the formula becomes (n*(1-s))^r. which is strictly smaller for any 0 < s <= 1, meaning you get a higher level of expected security (or possibly the same with fewer drives).