Do partitions needed to be unmounted when resizing a partition?

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http://serverfault.com – I have this article http://www.centos.org/docs/5/html/5.2/Deployment_Guide/s2-disk-storage-p... which is not clear to me. And also someone told me that swap space does not need to be disable if it is before the partition to resize. Modifications: This is the related question extend size of partition. I am resizing a partition to add the extra/unallocated 1500GB disk space on the same disk. And would be better not to do it with lvm if possible. I hope someone would enlighten me. Thanks (HowTos)