Ok so my emonpi (low-write 9.7.8 | 2016.11.10) stopped logging a few days ago, turns out /home/pi/data is full:
Filesystem Size Used Avail Use% Mounted on
/dev/mmcblk0p3 194M 186M 0 100% /home/pi/data
Looks like culprit is phpfina:
155M phpfina
Is there a way to increase the data fs, or alternately how can I decrease the data used on disk?
Ok I am being an idiot here… I am thinking that block device is a ramdisk but its a partition on the SDCard… of which of course I have not resized and have only 4GB of the 8GB card in use…
sudo emonSDexpand
now run… which will fix the issue I am sure! Adding this for the next person to make a tired mistake and need help to find 
With the latest image versions after installation does it automatically use the full 8Gb of a card without the need to run the expand command?
At present my one indicates this with build emonSD-30Oct18
Many thanks
I think you need to expand it.
I’ve made a note to review this with @glyn.hudson
I was not sure if the new image used the full card by default.
Anyway, started off the progress to see what happens…
Unlike older emonSD card images the root FS is no longer in read-only mode.
To preserve SD-card lifespan avoid installing any high write applications.
Log files in /var/log are mounted to tempfs in RAM
Emoncms data is logged to ~/data which is mounted to a low-write ext2 file-system
emonSD-30Oct18
pi@emonpi:~ $ sudo emonSDexpand
/usr/local/sbin/emonSDexpand: line 29: rpi-rw: command not found
======================================================
Current Disk Info:
Disk /dev/mmcblk0: 7.5 GiB, 8018460672 bytes, 15661056 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x50c2568e
Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 8192 96663 88472 43.2M c W95 FAT32 (LBA)
/dev/mmcblk0p2 98304 8290303 8192000 3.9G 83 Linux
/dev/mmcblk0p3 8290304 15558656 7268353 3.5G 83 Linux
======================================================
Proposed changes to be made:
SD card total disk size = 7.4677734375Gb
Data Partition size = 3.46582078934Gb
Are you sure you want to proceed? [Y/n] y
/usr/local/sbin/emonSDexpand: line 61: rpi-rw: command not found
Welcome to fdisk (util-linux 2.29.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): Partition number (1-3, default 3):
Partition 3 has been deleted.
Command (m for help): Partition type
p primary (2 primary, 0 extended, 2 free)
e extended (container for logical partitions)
Select (default p): Partition number (3,4, default 3): First sector (2048-15661055, default 2048): Last sector, +sectors or +size{K,M,G,T,P} (8290304-15661055, default 15661055):
Created a new partition 3 of type 'Linux' and of size 3.5 GiB.
Partition #3 contains a ext2 signature.
Command (m for help):
Disk /dev/mmcblk0: 7.5 GiB, 8018460672 bytes, 15661056 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x50c2568e
Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 8192 96663 88472 43.2M c W95 FAT32 (LBA)
/dev/mmcblk0p2 98304 8290303 8192000 3.9G 83 Linux
/dev/mmcblk0p3 8290304 15558656 7268353 3.5G 83 Linux
Command (m for help): The partition table has been altered.
Calling ioctl() to re-read partition table.
Re-reading the partition table failed.: Device or resource busy
The kernel still uses the old table. The new table will be used at the next reboot or after you run partprobe(8) or kpartx(8).
This error message can however be disregarded, because your system
is about to be rebooted, and the new partition table will then be
read by your operating system.
Writing the resize2fs_once script
======================================================================
So far, so good... in 20s your system will reboot
and resize the /home/pi/data filesystem to fill the resized partition.
**THIS OPERATION WILL TAKE UP TO 20 MINUTES**
When completed the Pi will poweroff and close down.
PLEASE DO NOT UNPLUG THE POWER FOR AT LEAST 30min
because it will likely result in an unusable filesystem.
======================================================================
