resize the disk from vsphere client,
in linux client do a
echo 1 > /sys/bus/scsi/devices/0\:0\:0\:0/rescan
# replace 0\:0\:0\:0 with your own disk scsi id and then
resize2fs /dev/sda
PS: In case a new disk was added to the SCSI bus you need to
echo "- - -" > /sys/class/scsi_host/host0/scan
PS: In case a new disk was added to the SCSI bus you need to
echo "- - -" > /sys/class/scsi_host/host0/scan