So I suggest you buy a more reliable SD card, ideally check This is one of the most complicated things but when done properly, it’s not too much work and it won’t cause any problems. But this is what you probably won’t need on a headless RPi.
Unless you have special requirements, there are only a few paths which needs to be writable. You definitely don’t want cron on your read-only RPi unless you have external hardware clock source, more about it later. You can then use logread command to read syslog ringbuffer from the memory when needed.
So let’s go through all steps required to make a truly, trouble-free read-only RPi: It’s a bad idea to set it up with an old software. You won’t need normal syslog text files on a read-only filesystem, either. Because the filesystem will be mounted read-only, there is nothing to be corrupted so filesystem check must be disabled. If you don’t have an external HW clock and use NTP time sync only and you do a change to the filesystem and reboot, filesystem check will see it as an update from the future, denying further boot, requiring manual action on the site.
RPi logs in to the server using a separate account and using SSH keys (so without a password) you can look up the relevant info online/google.I suggest you to set up SSH login from the RPi too so you can log to RPi from the server without password. To survive an unexpected poweroff, you need to have all filesystem mounted read-only (more about it later). even if you have your FS read-only, a cheap SD card can destroy the data on the card itself.Raspberry Pi is a nice, small device which can be used for various automation purposes, internet of things or as an advanced camera.I have been using 5 RPis as a camera with motion detection and post-processing.This application requires high reliability and it was a pretty long journey until all the issues were solved.
Here I am writing the most important things I have learned so you don’t need to go through the same stuff again (my cameras were placed on a remote location, making the whole process more complicated).