Disk space not considered

Hi,

I have several VM installed on VMware ESXi 6 and I have a nagios server on one of this VM. My problem is the that when I increase the disk space (20G --> 100G) of the VM where nagios is installed the new disk space is visible in VMware but for nagios there is still 20G in the disk.

I check with that command : df -h

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I don't know if that is VMware issue but I create the discussion anyway.

Thank for your help.