I needed to do this on the VPS and none of the provided solutions worked for me,

  this answer did the trick

https://serverfault.com/questions/551453/how-do-i-verify-that-my-hosting-provider-gave-me-ssds/551495#551495

so, it is about reading random data from the drive and assessing the time.

time for i in `seq 1 1000`; do
    dd bs=4k if=/dev/sda count=1 skip=$(( $RANDOM * 128 )) >/dev/null 2>&1;
done

here are my results for SSD

real    0m1.375s
user    0m0.285s
sys     0m0.944s

and HDD

real    0m14.249s
user    0m0.752s
sys     0m6.284s

I needed to do this on the VPS and none of the provided solutions worked for me, but this answer did the trick:

https://serverfault.com/questions/551453/how-do-i-verify-that-my-hosting-provider-gave-me-ssds/551495#551495

This just reads random data from the drive and assesses the time.

time for i in `seq 1 1000`; do
    dd bs=4k if=/dev/sda count=1 skip=$(( $RANDOM * 128 )) >/dev/null 2>&1;
done

NOTE: You may need sudo before the dd command, depending on your permissions.

Here are my results for an SSD:

real    0m1.375s
user    0m0.285s
sys     0m0.944s

And a HDD:

real    0m14.249s
user    0m0.752s
sys     0m6.284s

As you can see, the HDD takes about 10x the duration. This may not be reliable for some very fast HDD's, but in general, it will give you a good idea.

I needed to do this on the VPS and none of the provided solutions worked for me,

this answer did the trick

http://serverfault.com/questions/551453/how-do-i-verify-that-my-hosting-provider-gave-me-ssds/551495#551495

so, it is about reading random data from the drive and assessing the time.

time for i in `seq 1 1000`; do
    dd bs=4k if=/dev/sda count=1 skip=$(( $RANDOM * 128 )) >/dev/null 2>&1;
done

here are my results for SSD

real    0m1.375s
user    0m0.285s
sys     0m0.944s

and HDD

real    0m14.249s
user    0m0.752s
sys     0m6.284s

I needed to do this on the VPS and none of the provided solutions worked for me,

this answer did the trick

https://serverfault.com/questions/551453/how-do-i-verify-that-my-hosting-provider-gave-me-ssds/551495#551495

so, it is about reading random data from the drive and assessing the time.

time for i in `seq 1 1000`; do
    dd bs=4k if=/dev/sda count=1 skip=$(( $RANDOM * 128 )) >/dev/null 2>&1;
done

here are my results for SSD

real    0m1.375s
user    0m0.285s
sys     0m0.944s

and HDD

real    0m14.249s
user    0m0.752s
sys     0m6.284s