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Problem with btrfs filesystem and SNMP disk space sensors



I just upgraded from PRTG 14 to, and have run into a new problem with pre-existing SNMP Disk Free sensors. On Linux servers with a btrfs filesystem, the sensors report a disk space error, because the inode channel shows zero inodes. When I checked the servers, I discovered that "df -i" also reports zero inodes. This is wrong, and these servers all have plenty of inodes available. So this looks like a bug in the implementation of btrfs on Linux, or in the df command.

This is obviously a problem with btrfs, not PRTG, but I still need to be able to monitor disk space. The only solution I can come up with would be simply to delete the inode channels in the sensors, but it appears that I can't do that. Is this something that could be implemented? Or is there an alternative solution that I'm missing?

btrfs disk-free snmp

Created on Apr 22, 2015 7:56:35 PM

2 Replies



Following up on my original question, as an alternative approach, is there a Linux disk space sensor that will ignore inodes?

Created on Apr 23, 2015 7:27:29 PM




As channels cannot be deleted, you can hide channels from the charts and tables. Click on the inode channel you want to hide to get in the channel settings and mark Hide from Charts and Hide from Tables. Unfortunately, there is no sensor which ignores the inodes, so you would need to create a custom script here.

Best regards

Created on Apr 24, 2015 12:19:43 PM by  Felix Saure [Paessler Support]

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