| mftips@gmail.com 2006-01-20, 3:55 am |
| In Mainframes, MVS takes backup of files/datasets, every time they are
changed. Also it keeps backup of these changed versions at any point of
time. So, at any point of time we can recover deleted datasets as well
as its previous versions.
To find out how many versions of a dataset are available in backup,
enter the following command in TSO (Start 6) panel.
HLIST BCDS DSN ('Dataset Name')
or type the following in the command line
TSO HLIST BCDS DSN ('Dataset Name')
This will give the list of backups. Also, every backup has a backup
date and a GEN (Generation) no. associated with it.
For example, Assume PDS ' X' is last changed on 27/12/05 after
which MVS has taken backup of all the files/datasets. If PDS 'X'
has to be recovered without change on 27/12/05, then from the backup
list we need to get the
GEN( generation) No. for the backup date which is less than (27/12/05).
Let us assume the generation to be GEN (005).
So to recover that File or PDS, enter the following command in TSO
(Start 6) panel.
HRECOVER 'Original Dataset Name' GEN(005) NEWNAME.
or type the following in the command line
TSO HRECOVER 'Original Dataset Name' GEN(005) NEWNAME.
MVS will prompt for a new dataset name. Enter the new dataset name and
MVS will recover that version with the new name.
Note:
In case a deleted dataset needs to be recovered, enter the following
command in TSO (Start 6) panel.
HRECOVER 'Deleted dataset Name'
or type the following in the command line
TSO HRECOVER 'Deleted Dataset Name'
If MVS has that backup it will recover that with same name, i.e. the
latest version.
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