I have posted a few times in relation to installing a real time clock RTC on OMV on a Raspberry Pi. This guide is for OMV 3 (jessie) and the main things to note are:
- it's quite easy to get RTC working (far simpler than on OMV 2)
- No need to use or make changes to hwclock.sh
Below are the steps to install and configure:
1. Download, install and update OMV 3 on your RPi
2. Configure RPi to use NTP (date section of OMV GUI - set time to correct timezone)
3a. install RTC module on the RPi - the module is installed directly into the GPIO header at the corner. see attached image for correct position/pins
3b. enable the ic2 interface using the rasp-config tool. To enable iC2:
- Install raspi-config sudo apt-get install raspi-config
- run rasp-config - sudo raspi-config, go to advanced and turn on ic2
4. modify the file /boot/config.txt: sudo nano /boot/config.txt and add dtoverlay=i2c-rtc,ds3231 at end of file
5. modify the file /lib/udev/hwclock-set: sudo nano /lib/udev/hwclock-set and comment out the following code - this section of code is near the beginning of the file)
6. Final step is to remove fake-hwclock and configuration that uses it
sudo apt-get remove fake-hwclock
sudo rm /etc/cron.hourly/fake-hwclock
sudo update-rc.d -f fake-hwclock remove
sudo rm /etc/init.d/fake-hwclock
7. clear syslog and reboot.
8. after rebooting check hwclock is working using the command sudo hwclock -r The time returned by hwclock should be the same as system time. check they are sync'd
That's it. Good luck.