[CentOS] how to resize a partition of a disk define as a physical volume

Hello,

I have a CentOS VM with only one disk on a Xenserver.

The disk has 2 partitions:

/dev/xvda1 -> /boot /dev/xvda2 -> a physical volume for LVM

I added 5GB to this disk via Xencenter to extend /dev/xvda2. Usually I just have to do "pvresize /dev/xvda" to have the additional space added to the disk. But for some reason it does not work for this disk.

[root ~]# pvresize /dev/xvda Failed to find physical volume "/dev/xvda". 0 physical volume(s) resized / 0 physical volume(s) not resized

[root ~]# pvresize /dev/xvda2 Physical volume "/dev/xvda2" changed 1 physical volume(s) resized / 0 physical volume(s) not resized

Does someone have seen this problem before or could have an idea of the problem?

Thanks, Bernard