Installation guide

C H A P T E R 9 Storage and File Systems
293
Viewing and Manipulating Files in the /vmfs Directory
You can view and manipulate files under /vmfs in these mounted VMFS volumes
with ordinary file commands such as ls and cp. Although mounted VMFS volumes
may appear similar to any other file system such as ext3, VMFS is primarily intended to
store large files such as disk images. Unfortunately, the service console (which is based
on a Linux 2.4 kernel) does not support files greater than 2GB. nfs is known to run
into this limitation, while ftp, scp and cp are not affected by it. Thus, you should use
ftp, scp and cp for copying files to and from a VMFS volume, as long as the host file
system supports these large files.
Note: If you use the ls command inside a ftp session, the file size may be different
from the output of the ls -l command or vmkfstools -l command. This is
because ftp uses 32-bit values for file sizes, and the maximum file size it can display is
4GB. However, you can safely transfer any large files between ESX Server machines
with a ftp session. The entire file is correctly copied over.
VMFS Volumes
In ESX Server 2.1, a VMFS-2 volume can span multiple partitions, across the same or
multiple (up to 32) LUNs or physical disks. A VMFS-2 volume is a logical grouping of
physical extents. Each physical extent is part of a disk; for example, a physical disk
partition. That is, a physical extent is a disk partition that is part of a VMFS-2 volume.
By contrast, VMFS-1 volumes are limited to a single physical extent.
You can view the VMFS volumes on your ESX Server at any time by changing
directories to the /vmfs directory, then listing its contents. You can use vmkfstools
-P <VMFS_volume_label>, to obtain more details about your VMFS volume.
# cd /vmfs
# ls
vmhba0:0:0:2 vmhba0:0:0:6
The entries in the /vmfs directory are updated dynamically. Any changes you make
to VMFS-2 volumes through the VMware Management Interface are immediately
reflected in this directory.
For more details on vmkfstools, see Using vmkfstools on page 296.