332 lines
5.2 KiB
HTML
332 lines
5.2 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Rolling back a snapshot</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="EVMS User Guide"
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HREF="index.html"><LINK
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REL="UP"
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TITLE="Creating snapshots"
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HREF="evmscreatesnap.html"><LINK
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REL="PREVIOUS"
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TITLE="Deleting a snapshot"
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HREF="x1843.html"><LINK
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REL="NEXT"
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TITLE="Creating volumes"
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HREF="evmscreatevol.html"></HEAD
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><BODY
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><TR
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COLSPAN="3"
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>EVMS User Guide</TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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>Chapter 11. Creating snapshots</TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="evmscreatevol.html"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="sect1"
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><H1
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CLASS="sect1"
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><A
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NAME="AEN1847"
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></A
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>11.7. Rolling back a snapshot</H1
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><P
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>Situations can arise where a user wants to restore the original volume to
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the saved state of the snapshot. This action is called a rollback. One such scenario
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is if the data on the original is lost or corrupted. Snapshot rollback acts as a quick
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backup and restore mechanism, and allows the user to avoid a more lengthy restore
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operation from tapes or other archives.</P
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><P
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>Another situation where rollback can be particularly useful is when you are
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testing new software. Before you install a new software package, create a writeable
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snapshot of the target volume. You can then install the software to the snapshot
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volume, instead of to the original, and then test and verify the new software on the
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snapshot. If the testing is successful, you can then roll back the snapshot to the
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original and effectively install the software on the regular system. If there is a problem
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during the testing, you can simply delete the snapshot without harming the original
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volume.</P
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><P
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>You can perform a rollback when the following conditions are met:
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</P
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><P
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></P
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><UL
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><LI
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><P
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> Both the snapshot and the original volumes
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are unmounted and otherwise not in use.
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</P
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></LI
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><LI
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><P
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> There is only a single snapshot of an original.</P
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><P
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> If an original has multiple snapshots,
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all but the desired snapshot must be deleted before rollback can take place.
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</P
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></LI
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></UL
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><P
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>No options are available for rolling back snapshots.</P
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="AEN1859"
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></A
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>11.7.1. Using the EVMS GUI or Ncurses</H2
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><P
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>Follow these steps to roll back a snapshot with the EVMS GUI or Ncurses:</P
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><P
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></P
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><OL
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TYPE="1"
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><LI
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><P
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>Select
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<SPAN
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CLASS="guimenu"
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>Actions</SPAN
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>-><SPAN
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CLASS="guimenuitem"
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>Other</SPAN
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>-><SPAN
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CLASS="guimenuitem"
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>Storage Object Tasks</SPAN
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>+.+
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+ </P
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></LI
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><LI
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><P
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>Select the object "snap."</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Next</SPAN
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>.</P
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></LI
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><LI
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><P
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>Select <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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></P
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>.</LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Next</SPAN
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>.</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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> on the action panel.
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</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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> on the warning panel.
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</P
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></LI
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></OL
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><P
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>Alternatively, you can perform these same steps with the context-sensitive menus:</P
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><P
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></P
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><OL
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TYPE="1"
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><LI
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><P
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>From the Feature Objects panel, right click (or press
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<B
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CLASS="keycap"
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>Enter</B
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> on) the object "snap."</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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> on the popup menu.</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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> on the action panel.</P
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></LI
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><LI
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><P
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>Click or activate <SPAN
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CLASS="guibutton"
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>Rollback</SPAN
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> on the warning panel.</P
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></LI
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></OL
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></DIV
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><DIV
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CLASS="sect2"
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><H2
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CLASS="sect2"
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><A
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NAME="AEN1900"
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></A
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>11.7.2. Using the CLI</H2
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><P
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>Follow these steps to roll back a snapshot with the CLI:</P
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><P
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></P
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><OL
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TYPE="1"
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><LI
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><P
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>Issue the following command to the CLI:</P
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><TABLE
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BORDER="0"
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BGCOLOR="#E0E0E0"
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WIDTH="100%"
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><TR
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><TD
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><FONT
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COLOR="#000000"
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><PRE
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CLASS="programlisting"
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>task:rollback,snap</PRE
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></FONT
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></TD
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></TR
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></TABLE
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></LI
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><LI
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><P
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>Press <B
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CLASS="keycap"
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>Enter</B
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> to select "Rollback" (the default choice) at the warning message.</P
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></LI
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></OL
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></DIV
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
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SUMMARY="Footer navigation table"
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WIDTH="33%"
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ALIGN="left"
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HREF="x1843.html"
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ACCESSKEY="P"
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>Prev</A
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>Next</A
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WIDTH="33%"
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ALIGN="left"
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VALIGN="top"
|
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>Deleting a snapshot</TD
|
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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VALIGN="top"
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>Creating volumes</TD
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></TR
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></BODY
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> |