Pi2 / partition switching to RO by itself??

[Speedy2k]

Hi, I have amny RaspberryPi 2 Running from wall current but thru a Adafruit PowerBoost 1000C with a SanDisk Extreme 32GB MicroSD card. (SDSQXNE-032G-GN6MA). After some days about 6-7-8 days, The root partition is switching to RO by itself without rebooting. Those Pi2 are running MySQL, I wouldl iek to know if the PowerBoost 1000C can be the problem off causing bad sector on the SD card or those SD card are bad ? I have bought them on amazon maybe they are clone? What is the best known SD card on earth for long life? I only need 8 to 16 gigs? And what can can the root to switch to RO by itself without rebooting ??

[fsr]

Linux remounts local filesystems as read only as a self preservation measure if it detects errors.
check your system logs /var/log/syslog
almost certainly you are getting errors with the SD card.
backup now, get another sd card now

[Speedy2k]

But what can cause that?? I have got this behaviour from 3-4 machine right now in the last 2 weeks, Is the SD card i use are not good?

[fsr]

But what can cause that??

There is a very long list of possible causes and I would only be speculating as I have no information to go off...
Check your logs, find the error(s) look for a pattern.

My guess is you have a lot of IO. If something is causing a lot of IO it will wear out the SD cards pretty quickly.
Thats just a guess though, you need to examine and monitor till you get to the bottom of it. One thing is for sure, there will be a reason as you have 4 already.