Qsan Technology P300H61, Руководство пользователя

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Figure 5.4.4.1
On Linux and UNIX platform, a command named
sync can be used to make the operating
system flush data from write caching into disk. For Windows platform, Microsoft also
provides a tool –
sync , which can do exactly the same thing as the sync command in
Linux/UNIX. It will tell the OS to flush the data on demand. For more detail about sync
tool, please refer to: http://technet.microsoft.com/en-us/sysinternals/bb897438.aspx
Besides the
sync tool, Microsoft develops VSS (volume shadow copy service) to prevent
this issue. VSS is a mechanism for creating consistent point-in-time copies of data known
as shadow copies. It is a coordinator between backup software, application (SQL or
Exchange…) and storages to make sure the snapshot without the problem of data-
inconsistent.
For more detail about the VSS, please refer to
http://technet.microsoft.com/en-us/library/cc785914.aspx . QSAN P300H61 / P300H71
can support Microsoft VSS.
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What if the snapshot space is over?
Before using snapshot, a snapshot space is needed from RG capacity. After a period of
working snapshot, what if the snapshot size over the snapshot space of user defined?
There are two different situations: